Can't figure this out, any help? I don't think this is strtok, I pretty sure it is my code. I can't figure out what thought. Get and Set are causing sigsevg. If I put a printf() after num = strtof, etc, the num is right, but the other commands arent being interpreted right.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct
{
float height;
float width;
float length;
}Box;
void usage(void)
{
printf("\nUsage: [command] [parameter] [amount]\n");
printf("commands:\n\tSet\n\tGet\n");
printf("parameters:\n\theight\n\twidth\n\tlength\n");
}
int main()
{
usage();
Box box1 = {0,0,0};
int loop = 1;
float num;
char cp[65], *delims = " !##$%^&*():;/><.,\\?\"";
char *tok1, *tok2, *tok3, *temp;
beginning:
while(loop)
{
//Read the command from standard input
char str[65];
fgets(str, 64, stdin);
str[64] = 0;
//Tokenize the string
strncpy(cp, str, 64);
tok1 = strtok(cp, delims);
tok2 = strtok(NULL, delims);
tok3 = strtok(NULL, delims);
//Check if tok3 is float
num = strtof(tok3, &temp);
if(num != 0)
{
}
else
{
usage();
goto beginning;
}
if(tok1 == 'Get' && tok2 == 'height')
{
printf("%f", box1.height);
}
else if(tok1 == 'Get' && tok2 == 'width')
{
printf("%f", box1.width);
}
else if(tok1 == 'Get' && tok2 == 'length')
{
printf("%f", box1.length);
}
else if(tok1 == 'Get')
{
usage();
goto beginning;
}
if(tok1 == 'Set' && tok2 == 'height')
{
box1.height = num;
printf("%f", box1.height);
}
else if(tok1 == 'Set' && tok2 == 'width')
{
box1.width = num;
}
else if(tok1 == 'Set' && tok2 == 'length')
{
box1.length = num;
}
else if(tok1 == 'Set')
{
usage();
goto beginning;
}
}
return 0;
}
if(tok1 == 'Get' && tok2 == 'height')
C strings have to use double quotes, and you can't test them equal using ==, you should use strcmp:
if(strcmp(tok1, "Get")==0 && strcmp(tok2, "height")==0)
About strtof:
num = strtof(tok3, &temp);
If you didn't have to use temp, use a null pointer:
num = strtof(tok3, NULL);
And the piece of code using goto:
if(num != 0)
{
}
else
{
usage();
goto beginning;
}
goto is ugly, use continue instead:
if(num == 0)
{
usage();
continue;
}
Related
I'm writing a word, character, line counter for files in C. Im using a function get_counts to get these numbers. Right now I'm trying to get these values for two files. However, when I call it twice, the values don't reset to zero. I don't understand why because I declare the array to be {0,0,0} before I do any counting when I call the function. Here is my code. Currently just trying to get the line counter to work in print_counts. i'm sending it two files, one file has 3735 lines and the other file has 21. I keep getting an output of 3756.
int *get_counts(char *filename)
{
FILE *file = fopen(filename, "r");
if (file == NULL)
{
printf("NULL FILE");
exit(1);
}
int c;
bool whitespace = true;
static int arr[3] = {0,0,0};
for(;;)
{
c = fgetc(file);
if (c == EOF)
{
break;
}
else if (c == '\n')
{
arr[0]++;
}
else if (whitespace && !isspace(c))
{
arr[1]++;
whitespace = false;
}
else if (!whitespace && isspace(c))
{
whitespace = true;
}
arr[2]++;
}
fclose(file);
return arr;
}
void print_counts(int* show, int *count, char *name)
{
if (name[0] != '\0')
{
//int *myArray1 = get_counts(&name[0]);
if (show[0] == 1)
{
printf("%d", count[0]);
}
}
if (name[1] != '\0')
{
if (show[0] == 1)
{
printf("%d", count[0]);
}
}
}
int main(int argc, char **argv)
{
int argArray[argc];
char *nameArray[argc];
for (int i = 1; i < argc; i ++)
{
if (strcmp(argv[i], "-l") == 0)
{
argArray[0] = 1;
}
if (strcmp(argv[i], "-w") == 0)
{
argArray[1] = 1;
}
if (strcmp(argv[i], "-c") == 0)
{
argArray[2] = 1;
}
if (strcmp(argv[i], "alice.txt") == 0)
{
nameArray[0] = "alice.txt";
}
if (strcmp(argv[i], "anh.txt") == 0)
{
nameArray[1] = "anh.txt";
}
if ((strcmp(argv[i], "-l") != 0) && (strcmp(argv[i], "-c") != 0 ) && (strcmp(argv[i], "-w") != 0 ) && (strcmp(argv[i], "-w") != 0) && (strcmp(argv[i], "alice.txt") != 0) && (strcmp(argv[i], "anh.txt") != 0))
{
printf("error");
exit(1);
}
}
int *myArrayAlice = get_counts(nameArray[0]);
print_counts(argArray, myArrayAlice, *nameArray);
int *myArrayAnh = get_counts(nameArray[1]);
print_counts(argArray, myArrayAnh, *nameArray);
return 0;
}
I don't understand why because I declare the array to be {0,0,0}
before I do any counting when I call the function.
Because is defined as static, remove the static keyword switching to int *arr = calloc(3, sizeof(int); or passing arr[3] from main and calling memset(arr, 0, 3 * sizeof(int)); in the function if you prefer to avoid dynamic memory.
Hi I am completely stuck on this basic calculator. It runs almost perfectly but something goes wrong in the stack when I try inputting "5 / 5 + 9 * 2". The 1 from 5 / 5 seems to disappear when it is supposed to be addes to the 18 for the last loop. Happens for simular inputs like 2 * 2 - 9 / 2. Just need help finding this weird error that I have spent many hours trying to figure out with no luck! Thank you!
#include <stdio.h>
#include<string.h>
#include<stdlib.h>
#include <limits.h>
#include <curses.h>
#include<ctype.h>
struct StackNode
{
char* data;
struct StackNode* next;
};
struct StackNode* newNode(char* data)
{
struct StackNode* stackNode =
(struct StackNode*) malloc(sizeof(struct StackNode));
stackNode->data = data;
stackNode->next = NULL;
return stackNode;
}
int isEmpty(struct StackNode *root)
{
return !root;
}
void push(struct StackNode** root, char* data)
{
struct StackNode* stackNode = newNode(data);
stackNode->next = *root;
*root = stackNode;
printf("%s pushed to stack\n", data);
}
char* pop(struct StackNode** root)
{
if (isEmpty(*root))
return NULL;
struct StackNode* temp = *root;
*root = (*root)->next;
char* popped = temp->data;
free(temp);
printf("Popped: %s\n", popped);
return popped;
}
char* peek(struct StackNode* root)
{
if (isEmpty(root))
return NULL;
return root->data;
}
char buffer[64];
char *ca = &buffer[0];
size_t size = 64;
int bufferIndex;
int first = 0;
int isWhiteSpace (char c) {
if ((c == ' ') || (c == '\t') || (c == '\r')) {
return 1;
}
else {
return 0;
}
}
char* getToken() {
char* token = malloc(64);
int i = 0;
while ((isWhiteSpace(buffer[bufferIndex])) && bufferIndex < strlen(buffer)-1) {
bufferIndex++;
}
while (bufferIndex < strlen(buffer)-1) {
int num = isWhiteSpace(buffer[bufferIndex]);
if (num == 0) {
token[i] = buffer[bufferIndex];
i++;
bufferIndex++;
//printf("%s\n", token);
}
else {
bufferIndex++;
break;
}
}
token[i] = '\0';
first++;
return token;
}
int main() {
while (1) {
char* token = "test";
char* postFix = "test";
char* hold = malloc(64);
postFix = malloc(64);
int total = 0;
int pres1 = 0;
int pres2 = 0;
struct StackNode* root = NULL;
printf("Enter line: ");
getline(&ca,&size,stdin);
bufferIndex = 0;
if ((strcmp(token, "quit") == 0)) {
token = getToken();
if (strcmp(token, "") == 0) {
break;
}
else {
printf("Too many arguments. Try again.\n");
}
}
else {
while (strcmp(token, "") != 0) {
token = getToken();
//printf("%s\n", token);
//printf("Top of stack: %s\n", peek(root));
if (isdigit(*token) == 1) {
strcat(postFix, token);
strcat(postFix, " ");
printf("%s\n", postFix);
}
else if (peek(root) == NULL) {
push(&root, token);
}
else {
printf("Peek: %s\n", peek(root));
if (strcmp(token, "*") == 0) {
pres1 = 2;
}
else if (strcmp(token, "/") == 0) {
pres1 = 2;
}
else if (strcmp(token, "-") == 0) {
pres1 = 1;
}
else if (strcmp(token, "+") == 0) {
pres1 = 1;
}
else {
pres1 = 0;
}
if (strcmp(peek(root), "*") == 0) {
pres2 = 2;
}
else if (strcmp(peek(root), "/") == 0) {
pres2 = 2;
}
else if (strcmp(peek(root), "-") == 0) {
pres2 = 1;
}
else if (strcmp(peek(root), "+") == 0) {
pres2 = 1;
}
while((peek(root) != NULL) && (pres2 > pres1)) {
strcat(postFix, peek(root));
strcat(postFix, " ");
pop(&root);
printf("Postfix: %s\n", postFix);
}
push(&root, token);
}
}
do {
//printf("Peek in DO/WHILE: %s\n", peek(root));
strcat(postFix, peek(root));
strcat(postFix, " ");
pop(&root);
} while ((peek(root) != NULL));
printf("Postfix: %s\n", postFix);
//ca = NULL;
token = "1";
bufferIndex = 0;
for (int i = 0; i < strlen(postFix) + 1; i++) {
buffer[i] = postFix[i];
}
//size = strlen(postFix)+1;
//printf("TOKEN: %s\n", token);
while (strcmp(token, "") != 0) {
token = getToken();
if (isdigit(*token) == 1) {
//printf("--Token: %s\n", token);
push(&root, token);
}
else {
int operand1;
//operand1 = malloc(64);
int operand2;
//total = malloc(64);
printf("Peek: %s\n", peek(root));
operand2 = atoi(peek(root));
pop(&root);
printf("Operand2: %d\n", operand2);
if (strcmp(token, "") != 0) {
printf("Peek: %s\n", peek(root));
operand1 = atoi(peek(root));
pop(&root);
printf("Operand1: %d\n", operand1);
printf("Token: %s\n", token);
if (strcmp(token, "+") == 0) {
total = operand1 + operand2;
}
else if (strcmp(token, "/") == 0) {
total = operand1 / operand2;
}
else if (strcmp(token, "-") == 0) {
total = operand1 - operand2;
}
else if (strcmp(token, "*") == 0) {
total = operand1 * operand2;
}
sprintf(hold,"%d",total);
//printf("Peek: %s\n", peek(root));
push(&root, hold);
//pop(&root);
printf("Total: %d\n", total);
}
else {
//printf("Peek: %s\n", peek(root));
break;
}
}
}
}
printf("Total: %d\n", total);
}
return 0;
}
I am supposed to/am using this as a reference for the assignment: http://condor.depaul.edu/ichu/csc415/notes/notes9/Infix.htm
isdigit() should only be tested for zeroness
Instead of:
if (isdigit(*token) == 1) {
use:
if (isdigit((unsigned char)*token)) {
pointers make it easy to overwrite memory used elsewhere
The code does:
char* hold = malloc(64);
and then later on loops doing:
while (/* ... */) {
// ...
sprintf(hold,"%d",total);
push(&root, hold);
// ...
}
This causes all the values stored on the stack to share the same storage and to be overwritten whenever hold is changed.
The allocation must happen on every use:
char *hold;
// ...
while (/* ... */) {
// ...
hold = malloc(64);
sprintf(hold,"%d",total);
push(&root, hold);
// ...
}
This program should read rows and count operators, but counts wrong and can not find out where the errors are.
Help me find out the bugs and fix the program to be able to count rows and operators correctly.I've already tried several ways to fix it and it still counts wrong.
Current output:Broqt na operatorite e:1
Broqt na redovete e:1119
Expected output: Broqt na operatorite e:11
Broqt na redovete e:221
#ifndef _CRT_SECURE_NO_WARNINGS
#define _CRT_SECURE_NO_WARNINGS
#endif
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<ctype.h>
void cycleOperatorsCounter(FILE* inputStream, FILE* outputStream);
void counter(FILE* inputStream, FILE* outputStream);
int fileToFile(void);
int fileToScreen(void);
int screenToFile(void);
int screenToScreen(void);
void getFileName(char* fileName, int mode);
int menu() {
int i;
printf("----1. FILE TO FILE \n");
printf("----2. FILE TO SCREEN \n");
printf("----3. KBRD TO FILE \n");
printf("----4. KBRD TO SCREEN \n");
printf("----0. EXIT \n");
do {
printf("SELECT OPTION: ");
fflush(stdin);
scanf("%i", &i);
} while (i < 0 || i> 4);
return i;
}
int main(void) {
while (1) {
system("cls");
switch (menu()) {
case 1: fileToFile();
break;
case 2: fileToScreen();
break;
case 3: screenToFile();
break;
case 4: screenToScreen();
break;
default:
return 0;
}
system("pause");
}
}
void getFileName(char* fileName, int mode) {
while (1) {
fflush(stdin);
if (mode == 1) {
printf("Input file name(.C): ");
gets(fileName);
if (fileName[strlen(fileName) - 2] == '.' && toupper(fileName[strlen(fileName) - 1]) == 'C') {
return;
}
}
else {
printf("Output File: ");
gets(fileName);
return;
}
}
}
int fileToFile(void) {
char inputFileName[256], outputFileName[256];
FILE *inputStream, *outputStream;
getFileName(inputFileName, 1);
if (!(inputStream = fopen(inputFileName, "r"))) {
fprintf(stderr, "Error opening file!\n");
return -1;
}
getFileName(outputFileName, 2);
if (!(outputStream = fopen(outputFileName, "w"))) {
fprintf(stderr, "Error opening file!\a\n");
return -1;
}
cycleOperatorsCounter(inputStream, outputStream);
rewind(inputStream);
counter(inputStream, outputStream);
fclose(inputStream);
fclose(outputStream);
printf("Results saved to \"%s\".\n", outputFileName);
return 0;
}
int fileToScreen(void) {
char inputFileName[256];
FILE* inputStream;
getFileName(inputFileName, 1);
if (!(inputStream = fopen(inputFileName, "r"))) {
fprintf(stderr, "Error opening file!\n");
return -1;
}
cycleOperatorsCounter(inputStream, stdout);
rewind(inputStream);
counter(inputStream, stdout);
fclose(inputStream);
return 0;
}
int screenToFile(void) {
char outputFileName[256];
FILE *outputStream, *tempStream;
char str[999];
tempStream = fopen("temp.tmp", "w");
fflush(stdin);
printf("Napishete \"KRAI\" na nov red, kogato vuvedete teksta\n");
while (1) {
gets(str);
if (!strcmp(str, "KRAI")) {
fclose(tempStream);
tempStream = fopen("temp.tmp", "r");
break;
}
fprintf(tempStream, "%s\n", str);
}
getFileName(outputFileName, 2);
if (!(outputStream = fopen(outputFileName, "w"))) {
fprintf(stderr, "Error opening file!\a\n");
return -1;
}
cycleOperatorsCounter(tempStream, outputStream);
rewind(tempStream);
counter(tempStream, outputStream);
fclose(tempStream);
fclose(outputStream);
printf("Results saved to \"%s\".\n", outputFileName);
return 0;
}
int screenToScreen(void) {
FILE *tempStream;
char str[999];
tempStream = fopen("temp.tmp", "w");
fflush(stdin);
printf("Napishete \"KRAI\" na nov red, kogato vuvedete teksta\n");
while (1) {
gets(str);
if (!strcmp(str, "KRAI")) {
fclose(tempStream);
tempStream = fopen("temp.tmp", "r");
break;
}
fprintf(tempStream, "%s\n", str);
}
cycleOperatorsCounter(tempStream, stdout);
rewind(tempStream);
counter(tempStream, stdout);
fclose(tempStream);
return 0;
}
void cycleOperatorsCounter(FILE* inputStream, FILE* outputStream) {
char str[1000];
int cycleCounter = 0;
unsigned i;
while (fgets(str, sizeof(str), inputStream) != NULL) {
for (i = 0; i < strlen(str); i++) {
if ((str[i-1] == ' ' || str[i-1] == '\n' || str[i-1] == '\t' || i==0) &&
(str[i] == 'i') && (str[i + 1] == 'f') && (str[i+3] == ' ' || str[i+3] ==
'\n' || str[i+3] == '\t')) {
cycleCounter++;
}
if ((str[i-1] == ' ' || str[i-1] == '\n' || str[i-1] == '\t' ||
i==0)
&& (str[i] == 'e') && (str[i + 1] == 'l') && (str[i + 2] == 's')
&& (str[i + 3] == 'e')
&& (str[i+5] == ' ' || str[i+6] == '\n' || str[i+7] ==
'\t')) {
cycleCounter++;
}
}
}
fprintf(outputStream, "Broqt na operatorite za cikul e: %d\n",
cycleCounter);
}
void counter(FILE* inputStream, FILE* outputStream) {
char str[1000];
int Counter = 0;
unsigned i;
while (fgets(str, sizeof(str), inputStream) != NULL) {
for (i = 0; i < strlen(str); i++) {
{
if ((str[i-1] == ' ' || str[i-1] == '\n' || str[i-1] == '\t' || i==0))
{
Counter++;
}
}
}
}
fprintf(outputStream, "Broqt na redovete e: %d\n", Counter);
}
This is prefaced by my top comments.
That is, finding the if and the else is more easily done with strtok and strcmp.
And, to count rows/lines, simply doing fgets and counting or doing fgetc and counting the \n will work.
Hopefully, this will get you farther:
void
cycleOperatorsCounter(FILE *inputStream, FILE *outputStream)
{
char *bp;
char *tok;
char str[1000];
int cycleCounter = 0;
while (fgets(str, sizeof(str), inputStream) != NULL) {
bp = str;
while (1) {
tok = strtok(bp," \t\n");
if (tok == NULL)
break;
bp = NULL;
if (strcmp(tok,"if") == 0) {
cycleCounter++;
continue;
}
if (strcmp(tok,"else") == 0) {
cycleCounter++;
continue;
}
}
}
fprintf(outputStream, "Broqt na operatorite za cikul e: %d\n",
cycleCounter);
}
void
counter(FILE *inputStream, FILE *outputStream)
{
int Counter = 0;
// count number of lines
// NOTE: either of these should work:
#if 1
char str[1000];
while (fgets(str, sizeof(str), inputStream) != NULL)
++Counter;
#else
while (1) {
int chr = fgetc(inputStream);
if (chr == EOF)
break;
if (chr == '\n')
++Counter;
}
#endif
fprintf(outputStream, "Broqt na redovete e: %d\n", Counter);
}
So, essentially I have two files:
File 1:
//
// main.c
// frederickterry
//
// Created by Rick Terry on 1/15/15.
// Copyright (c) 2015 Rick Terry. All rights reserved.
//
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int size (char *g) {
int ofs = 0;
while (*(g+ofs) != '\0') {
++ofs;
}
return ofs;
}
int parse(char *g) {
// Setup
char binaryConnective;
int negated = 0;
// Looking for propositions
int fmlaLength = size(g);
if(fmlaLength == 0) {
return 1;
}
if(fmlaLength == 1) {
if(g[0] == 'p') {
return 1;
} else if (g[0] == 'q') {
return 1;
} else if (g[0] == 'r') {
return 1;
} else {
return 0;
}
}
// Now looking for negated preposition
if(fmlaLength == 2) {
char temp[100];
strcpy(temp, g);
if(g[0] == '-') {
negated = 1;
int negatedprop = parse(g+1);
if(negatedprop == 1) {
return 2;
}
}
}
// Checking if Binary Formula
char arrayleft[50];
char arrayright[50];
char *left = "";
char *right = "";
int numLeft = 0;
int numRight = 0;
int bclocation = 0;
int binarypresent = 0;
if(fmlaLength != 1 && fmlaLength != 2) {
if(g[0] == '-') {
int negatedBinary = parse(g+1);
if(negatedBinary == 1 || negatedBinary == 2 || negatedBinary == 3) {
return 2;
} else {
return 0;
}
}
int i = 0;
int l = 0;
int p = strlen(g);
for(l = 0; l < strlen(g)/2; l++) {
if(g[l] == '(' && g[p-l-1] == ')') {
i++;
}
}
for(int q = i; q < strlen(g); q++) {
if(g[q] == '(') {
numLeft++;
} else if(g[q] == ')') {
numRight++;
}
arrayleft[q] = g[q];
//printf("%c", arrayleft[i]);
//printf("%s", left);
if((numRight == numLeft) && (g[q+1] == 'v' || g[q+1] == '>' || g[q+1] == '^')) {
arrayleft[q+1] = '\0';
bclocation = q+1;
binaryConnective = g[q+1];
binarypresent = 1;
// printf("The binary connecive is: %c\n", binaryConnective);
break;
}
}
if(binarypresent == 0) {
return 0;
}
int j = 0;
for(int i = bclocation+1; i < strlen(g)-1; i++) {
arrayright[j] = g[i];
j++;
}
arrayright[j] = '\0';
left = &arrayleft[1];
right = &arrayright[0];
//printf("Printed a second time, fmla 1 is: %s", left);
int parseleft = parse(left);
// printf("Parse left result: %d\n", parseleft);
if(parseleft == 0) {
return 0;
}
int parseright = parse(right);
if(parseright == 0) {
return 0;
}
// printf("Parse right result: %d\n", parseleft);
if(negated == 1) {
return 2;
} else {
return 3;
}
}
return 0;
}
int type(char *g) {
if(parse(g) == 1 ||parse(g) == 2 || parse(g) == 3) {
if(parse(g) == 1) {
return 1;
}
/* Literals, Positive and Negative */
if(parse(g) == 2 && size(g) == 2) {
return 1;
}
/* Double Negations */
if(g[0] == '-' && g[1] == '-') {
return 4;
}
/* Alpha & Beta Formulas */
char binaryConnective;
int numLeft = 0;
int numRight = 0;
int bclocation = 0;
int binarypresent = 0;
int i = 0;
if(g[0] == '(') {
i++;
}
if(g[0] == '-') {
i++;
if(g[1] == '(') {
i++;
}
}
for(i; i < strlen(g); ++i) {
if(g[i] == '(') {
numLeft++;
} else if(g[i] == ')') {
numRight++;
}
if(numRight == numLeft) {
if(g[i+1] == 'v' || g[i+1] == '>' || g[i+1] == '^') {
bclocation = i+1;
binaryConnective = g[i+1];
binarypresent = 1;
break;
}
}
}
/* Connective established */
if(binaryConnective == '^') {
if(g[0] == '-') {
return 3;
} else {
return 2;
}
} else if(binaryConnective == '>') {
if(g[0] == '-') {
return 2;
} else {
return 3;
}
} else if (binaryConnective == 'v') {
if(g[0] == '-') {
return 2;
} else {
return 3;
}
}
}
return 0;
}
char bin(char *g) {
char binaryConnective;
char arrayLeft[50];
int numLeft = 0;
int numRight = 0;
int bclocation = 0;
int i = 0;
if(g[0] == '(') {
i++;
}
if(g[0] == '-') {
i++;
if(g[1] == '(') {
i++;
}
}
for(i; i < strlen(g); ++i) {
if(g[i] == '(') {
numLeft++;
} else if(g[i] == ')') {
numRight++;
}
int j = 0;
arrayLeft[j++] = g[i];
if(numRight == numLeft) {
if(g[i+1] == 'v' || g[i+1] == '>' || g[i+1] == '^') {
arrayLeft[i+1] = '\0';
bclocation = i+1;
binaryConnective = g[i+1];
return binaryConnective;
}
}
}
return binaryConnective;
}
char *partone(char *g) {
char binaryConnective;
char arrayLeft[50];
char arrayRight[50];
int numLeft = 0;
int numRight = 0;
int bclocation = 0;
int i = 0;
if(g[0] == '(') {
i++;
}
if(g[0] == '-') {
i++;
if(g[1] == '(') {
i++;
}
}
int j = 0;
for(i; i < strlen(g); ++i) {
if(g[i] == '(') {
numLeft++;
} else if(g[i] == ')') {
numRight++;
}
arrayLeft[j] = g[i];
if(numRight == numLeft) {
if(g[i+1] == 'v' || g[i+1] == '>' || g[i+1] == '^') {
arrayLeft[j+1] = '\0';
bclocation = i+1;
binaryConnective = g[i+1];
break;
}
}
j++;
}
int m = 0;
for(int k = bclocation+1; k < strlen(g)-1; k++) {
arrayRight[m] = g[k];
m++;
}
arrayRight[m] = '\0';
char* leftSide = &arrayLeft[0];
// printf("%s\n", leftSide);
// printf("%s\n", rightSide);
int k = 0;
k++;
return leftSide;
}
char *parttwo(char *g) {
char binaryConnective;
char arrayLeft[50];
char arrayRight[50];
int numLeft = 0;
int numRight = 0;
int bclocation = 0;
int i = 0;
if(g[0] == '(') {
i++;
}
if(g[0] == '-') {
i++;
if(g[1] == '(') {
i++;
}
}
int j = 0;
for(i; i < strlen(g); ++i) {
if(g[i] == '(') {
numLeft++;
} else if(g[i] == ')') {
numRight++;
}
arrayLeft[j] = g[i];
if(numRight == numLeft) {
if(g[i+1] == 'v' || g[i+1] == '>' || g[i+1] == '^') {
arrayLeft[j+1] = '\0';
bclocation = i+1;
binaryConnective = g[i+1];
break;
}
}
j++;
}
int m = 0;
int n = size(g) - 1;
if(g[strlen(g)-1] != ')') {
n++;
}
for(int k = bclocation+1; k < n; k++) {
arrayRight[m] = g[k];
m++;
}
arrayRight[m] = '\0';
char* leftSide = &arrayLeft[0];
char* rightSide = &arrayRight[0];
// printf("%s\n", leftSide);
// printf("%s\n", rightSide);
return rightSide;
}
char *firstexp(char *g) {
char* left = partone(g);
char leftArray[50];
int i = 0;
for(i; i < strlen(left); i++) {
leftArray[i] = left[i];
}
leftArray[i] = '\0';
char binConnective = bin(g);
int typeG = type(g);
if(typeG == 2) {
if(binConnective == '^') {
return &leftArray;
} else if(binConnective == '>') {
return &leftArray;
}
} else if(typeG == 3) {
if(binConnective == 'v')
return &leftArray;
}
char temp[50];
for(int i = 0; i < strlen(leftArray); i++) {
temp[i+1] = leftArray[i];
}
temp[0] = '-';
char* lefttwo = &temp[0];
if(typeG == 2) {
if(binConnective == 'v') {
return lefttwo;
}
} else if(typeG == 3) {
if(binConnective == '>' || binConnective == '^') {
return lefttwo;
}
}
return "Hello";
}
char *secondexp(char *g) {
// char binaryConnective = bin(g);
// char* right = parttwo(g);
// char rightArray[50];
// int i = 0;
// for(i; i< strlen(right); i++) {
// rightArray[i+1] = right[i];
// }
// rightArray[i] = '\0';
// int typeG = type(g);
// if(type(g) == 2) {
// if(binaryConnective == '^') {
// return &rightArray;
// }
// } else if(type(g) == 3) {
// if(binaryConnective == 'v' || binaryConnective == '>') {
// return &rightArray;
// }
// }
return "Hello";
}
typedef struct tableau tableau;
\
\
struct tableau {
char *root;
tableau *left;
tableau *right;
tableau *parent;
int closedbranch;
};
int closed(tableau *t) {
return 0;
}
void complete(tableau *t) {
}
/*int main(int argc, const char * argv[])
{
printf("Hello, World!\n");
printf("%d \n", parse("p^q"));
printf("%d \n", type("p^q"));
printf("%c \n", bin("p^q"));
printf("%s\n", partone("p^q"));
printf("%s\n", parttwo("p^q"));
printf("%s\n", firstexp("p^q"));
printf("Simulation complete");
return 0;
}*/
File 2:
#include <stdio.h>
#include <string.h> /* for all the new-fangled string functions */
#include <stdlib.h> /* malloc, free, rand */
#include "yourfile.h"
int Fsize = 50;
int main()
{ /*input a string and check if its a propositional formula */
char *name = malloc(Fsize);
printf("Enter a formula:");
scanf("%s", name);
int p=parse(name);
switch(p)
{case(0): printf("not a formula");break;
case(1): printf("a proposition");break;
case(2): printf("a negated formula");break;
case(3): printf("a binary formula");break;
default: printf("what the f***!");
}
printf("\n");
if (p==3)
{
printf("the first part is %s and the second part is %s", partone(name), parttwo(name));
printf(" the binary connective is %c \n", bin(name));
}
int t =type(name);
switch(t)
{case(0):printf("I told you, not a formula");break;
case(1): printf("A literal");break;
case(2): printf("An alpha formula, ");break;
case(3): printf("A beta formula, ");break;
case(4): printf("Double negation");break;
default: printf("SOmewthing's wrong");
}
if(t==2) printf("first expansion fmla is %s, second expansion fmla is %s\n", firstexp(name), secondexp(name));
if(t==3) printf("first expansion fmla is %s, second expansion fmla is %s\n", firstexp(name), secondexp(name));
tableau tab;
tab.root = name;
tab.left=0;
tab.parent=0;
tab.right=0;
tab.closedbranch=0;
complete(&tab);/*expand the root node then recursively expand any child nodes */
if (closed(&tab)) printf("%s is not satisfiable", name);
else printf("%s is satisfiable", name);
return(0);
}
If you look at the first file, you'll see a method called * firstexp(char * g).
This method runs perfectly, but only if another method called * secondexp(char * g) is commented out.
If * secondexp(char * g) is commented out, then *firstexp runs like this:
Enter a formula:((pvq)>-p)
a binary formula
the first part is (pvq) and the second part is -p the binary connective is >
A beta formula, first expansion fmla is -(pvq), second expansion fmla is Hello
((pvq)>-p) is satisfiableProgram ended with exit code: 0
otherwise, if *secondexp is not commented out, it runs like this:
Enter a formula:((pvq)>-p)
a binary formula
the first part is (pvq) and the second part is -p the binary connective is >
A beta formula, first expansion fmla is \240L, second expansion fmla is (-
((pvq)>-p) is satisfiable. Program ended with exit code: 0
As you can see, the outputs are completely different despite the same input. Can someone explain what's going on here?
In the commented-out parts of secondexp and in parttwo, you return the address of a local variable, which you shouldn't do.
You seem to fill a lot of ad-hoc sized auxiliary arrays. These have the problem that they might overflow for larger expressions and also that you cannot return them unless you allocate them on the heap with malloc, which also means that you have to free them later.
At first glance, the strings you want to return are substrings or slices of the expression string. That means that the data for these strings is already there.
You could (safely) return pointers into that string. That is what, for example strchr and strstr do. If you are willing to modify the original string, you could also place null terminators '\0' after substrings. That's what strtok does, and it has the disadvantage that you lose the information at that place: If you string is a*b and you modify it to a\0b, you will not know which operator there was.
Another method is to create a struct that stores a slice as pointer into the string and a length:
struct slice {
const char *p;
int length;
};
You can then safely return slices of the original string without needing to worry about additional memory.
You can also use the standard functions in most cases, if you stick to the strn variants. When you print a slice, you can do so by specifying a field width in printf formats:
printf("Second part: '%.*s'\n", s->length, s->p);
In your parttwo() function you return the address of a local variable
return rightSide;
where rightSide is a pointer to a local variable.
It appears that your compiler gave you a warning about this which you solved by making a pointer to the local variabe arrayRight, that may confuse the compiler but the result will be the same, the data in arrayRight will no longer exist after the function returns.
You are doing the same all over your code, and even worse, in the secondexp() function you return a the address of a local variable taking it's address, you are not only returning the address to a local variabel, but also with a type that is not compatible with the return type of the function.
This is one of many probable issues that your code may have, but you need to start fixing that to continue with other possible problems.
Note: enable extra warnings when compiler and listen to them, don't try to fool the compiler unless you know exactly what you're doing.
I need to convert infix to postfix and evaluate postfix expression. When reading from a file, I should be able to evaluate multiple expressions at once. But when I run it and it encounters an expression that is not well-formed in the sense that there are more closed parentheses than open ones, it evaluates that expression 2 or 3 times.
Code:
#include <stdio.h>
#include <conio.h>
#include <ctype.h>
#include <string.h>
#include <stdlib.h>
#define MAX 1000
typedef struct stack
{
int data[MAX];
int top;
} stack;
int priority(char);
void init(stack*);
int empty(stack*);
int full(stack*);
char pop(stack*);
void push(stack*, char);
char top(stack*);
void add(char*, char, int);
void keyboard();
void read_file();
int change(char);
void pushYO(double);
double popYO();
stack s;
char x;
int i, token, topYO = -1;
double result[MAX];
char filepath[MAX];
int main()
{
char choice;
init(&s);
system("CLS");
printf("[1] Keyboard \n[2] Read from text file \n[3] Exit \n");
scanf("%c", &choice);
if(choice != '1' && choice != '2' && choice != '3')
{
main();
}
else if(choice == '1')
{
keyboard();
}
else if(choice == '2')
{
read_file();
}
else if(choice == '3')
{
printf("\nThank you for using Kei Shirabe's \ninfix to postfix converter and evaluator! :)\n");
exit(0);
}
}
void keyboard() //the keyboard input version. this works fine
{
//code here
}
void read_file()
{
int z, count, form, paren;
double one, two, three = 1;
char infx[MAX];
char pofx[MAX];
char choice;
FILE *text = fopen("text.txt", "a");
printf("Enter path of file:");
scanf("%s",&filepath);
FILE *textYO = fopen(filepath, "r");
if((textYO) == NULL)
{
printf("\nError! Unable to open %s\n\n", filepath);
}
else
{
while((fgets(infx, MAX, textYO))!= NULL)
{
form = -1, paren = 0, count = 0, z = 0;
infx[
strlen(infx)-1] = '\0';
for (i=0; i<strlen(infx); i++)
{
if((token = infx[i]) != '\n')
{
if(isalnum(token))
{
form++;
}
else
{
if(token == '(')
{
paren++;
}
else if(token == ')')
{
paren--;
}
else
{
form--;
}
}
if (paren < 0)
{
printf("%s", infx);
fprintf(text, "%s", infx);
printf("\n\nError! Not well formed :( \n-----------------\n");
fprintf(text, "\n\nError! Not well formed :( \n-----------------\n");
}
else
if(isalnum(token))
{
add(pofx, token, count);
count++;
}
else
if(token == '(')
{
push(&s, '(');
}
else
{
if(token == ')')
while((x = pop(&s)) != '(')
{
add(pofx, x, count);
count++;
}
else
if(token == '^')
{
push(&s, token);
}
else
{
while(priority(token) <= priority(top(&s)) && !empty(&s))
{
x = pop(&s);
add(pofx, x, count);
count++;
}
push(&s, token);
}
}
}
else
{
while(!empty(&s))
{
x = pop(&s);
add(pofx, x, count);
count++;
}
}
}
if(form != 0 || paren != 0)
{
printf("%s", infx);
fprintf(text, "%s", infx);
printf("\n\nError! Not well formed :( \n-----------------\n");
fprintf(text, "\n\nError! Not well formed :( \n-----------------\n");
}
else
{
form = -1, paren = 0;
printf("%s", infx);
fprintf(text, "%s", infx);
printf("\n\nPostfix: %s \n\n", pofx);
fprintf(text, "\n\nPostfix: %s\n\n", pofx);
while((token = pofx[z++]) != '\0')
{
three = 1;
if(!isdigit(token) && !isalpha(token))
{
two = popYO();
one = popYO();
switch(token)
{
case '+':
pushYO(one+two); break;
case '-':
pushYO(one-two); break;
case '*':
pushYO(one*two); break;
case '/':
pushYO(one/two); break;
case '^':
if (two > 0)
{
for(i=0;i<two;i++)
{
three = three * one;
}
pushYO(three);
three = 1; break;
}
else
{
for(i=0;i<(two-(2*two));i++)
{
three = three * one;
}
pushYO((1/three));
three = 1; break;
}
}
}
else if(isalpha(token))
{
if(isupper(token))
{
pushYO(token - '#');
}
if(islower(token))
{
pushYO(token - change(token));
}
}
else
{
pushYO(token - '0');
}
}
printf("Result: %lf\n-----------------\n", result[topYO]);
fprintf(text, "Result: %lf\n-----------------\n", result[topYO]);
}
}
}
fclose(text);
fclose(textYO);
printf("\nRun again? \n[1] Yes \n[any other key] No\n");
scanf("%c", &choice);
scanf("%c", &choice);
if(choice == '1')
{
main();
}
else
{
printf("\nThank you for using Kei Shirabe's \ninfix to postfix converter and evaluator! :)\n");
exit(0);
}
}
//other functions down here, not important
Sample text file (and yes there is an extra space at the end):
(1+2))
(1+2*3)
For this text file, the expression (1+2)) is evaluated three times, each result being "Not well formed". The last expression works as expected.
Any help please?