Caesar cipher printing out numbers instead of decrypted Text? in C - c

So I have this caesar cipher program, however when I run it it only prints out numbers instead of the decrypted text. Anyone know what I am missing? I believe there might be something wrong in the bool solved function.
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include "rotUtils.h"
bool solved( char decodearr[], char dictarr[][30], int size1, int size2){
char* compared;
bool result = false;
for(int j = 0; j < size2; j++){
compared = strstr( decodearr, dictarr[j]);
}
if( compared != '\0'){
result = true;
}
return result;
}
int decode( char codearr[], char dictarr[][30], int size1, int size2)
{
bool solution = false;
int key = -50;
char decodearr[10000];
while(solution == false && key < 51)
{
for( int i = 0; i < size1; i++)
{
if(!isspace(codearr[i]))
{
decodearr[i] = rotate(codearr[i], key);
}
else
decodearr[i] = codearr[i];
}
solution = solved( decodearr, dictarr, size1, size2);
if( solution == false)
{
key++;
}
}
for( int j = 0; j < size1; j++)
{
codearr[j] = decodearr[j];
}
return key;
}
int main( int argc, char* argv[])
{
char* file = argv[1];
char* dictionary = argv[2];
char code[10000];
char dict[30000][30];
FILE* codeFile;
codeFile = fopen(file, "r");
int i = 0;
int j = 0;
int key;
FILE* dictFile;
dictFile = fopen(dictionary, "r");
while(!feof(codeFile))
{
code[i] = fgetc(codeFile);
i++;
}
code[ i + 1] = '\0';
fclose(codeFile);
while(!feof(dictFile))
{
fscanf(dictFile, "%s", dict[j]);
j++;
}
key = decode(code, dict, i, j);
fclose(dictFile);
for(int k = 0; k < i; k++)
{
printf("%d", code[k]);
}
printf( "\nThe key is: %d\n", key);
return 0;
}

printf("%d", code[k]); means "print out the decimal digits that represent the integer code[k]".
If you want "print out the character that represents the integer code[k], then you'd want the %c format specifier instead: printf("%c", code[k]);

You only ever print numbers
printf("%d", code[k]);
perhaps try
printf("%c", code[k]);
which prints the character that number represents.

Just use "%c" instead of "%d" in your code when you want to print code[k].
Good luck!

Related

Functions fopen/calloc/malloc and and ways of their replacement

I want to make a simple program (but difficult for me), which will find contacts by letters (parts of the name are entered using numbers) and by numbers (parts of the number). Input - numbers, from the standard input (txt file), output - contacts that contain these numbers (letters). The contact file looks like
(name)
(number)
(name)
(…)
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#define MAX_NAME (128)
#define MAX_NUM (32)
/*
IN :
contacts.txt :
Sad Mirrow
38074025
Deniel Kovalski
78032596
Miky Trance
88055535
Martin Worried
77432651
96 [key number from standard entry]
OUT:
Deniel Kovalski
[because 96 matches in his number]
Martin Worried
[96 matches in his name Wo]
*/
typedef struct Contact {
char* name;
char* number;
} Contact;
char matchTable[10][9] = {
"0+", "1", "2abcABC", "3defDEF", "4ghiGHI",
"5jklJKL", "6mnoMNO", "7pqrsPQRS", "8tuvTUV", "9wxyWXY"
};
bool find(char c, char key){
int j = key - '0';
for (int i = 0; matchTable[j][i] != '\0'; i++){
if (c == matchTable[j][i])
return true;
}
return false;
}
bool matches(char* src, char* key){
unsigned int i,j;
for (i = 0; src[i] != '\0'; i++){
int tmp = i;
for (j = 0; key[j] != '\0'; j++){
if (find(src[tmp], key[j]))
tmp++;
else
break;
}
if (j == strlen(key))
return true;
}
return false;
}
int main(){
char key[MAX_NUM];
scanf("%s", key);
size_t arrSize = 32;
Contact* contacts = malloc(arrSize * sizeof(Contact));
int k = 0;
size_t nameSize = MAX_NAME;
size_t numSize = MAX_NUM;
char *nameBuf = malloc(MAX_NAME);
char *numBuf = malloc(MAX_NUM);
FILE* f = fopen("contacts.txt", "r");
while (fgets(nameBuf, nameSize, f)
&& fgets(numBuf, numSize, f)){
contacts[k].name = malloc(MAX_NAME);
contacts[k].number = malloc(MAX_NUM);
strcpy(contacts[k].name, nameBuf);
strcpy(contacts[k].number, numBuf);
k++;
if (k == arrSize);
arrSize <<= 1;
contacts = realloc(contacts, arrSize * sizeof(Contact));
}
for (int i = 0; i < k; i++){
bool matchesName = matches(contacts[i].name, key);
bool matchesNumber = matches(contacts[i].number, key);
if (matchesName || matchesNumber)
printf("%s\n", contacts[i].name);
}
for (int i = 0; i < k; i++){
free(contacts[i].name);
free(contacts[i].number);
}
free(contacts);
free(nameBuf);
free(numBuf);
fclose(f);
return 0;
}
At first we did as we could. Then was a time to fulfill the conditions of the task and the problem came. It needs to be done without malloc/calloc/fopen. I tried to fix everything, but I ran into a problem that the program does not work and it seems to me that I'm confused.
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#define MAX_NAME (128)
#define MAX_NUM (64)
struct Folio
{
char name[1000];
char num[1000];
};
static char matchTable[10][9] = {
"0+", "1", "2abcABC", "3defDEF", "4ghiGHI",
"5jklJKL", "6mnoMNO", "7pqrsPQRS", "8tuvTUV", "9wxyWXY"
};
int find(char c, char key){
int j = key - '0';
for (int i = 0; matchTable[j][i] != '\0'; i++){
if (c == matchTable[j][i])
return 1;
}
return 0;
}
int matches(char* src, char* key){
unsigned int i,j;
for (i = 0; src[i] != '\0'; i++){
unsigned int tmp = i;
for (j = 0; key[j] != '\0'; j++){
if (find(src[tmp], key[j]))
tmp++;
else
break;
}
if (j == strlen(key))
return 1;
}
return 0;
}
int main(){
char key[MAX_NUM];
scanf("%s", key);
struct Folio contacts[42]; //Entry entries[42]
int contacts_count = 0; //entries_count = 0;
//FILE* f = fopen("seznam.txt", "r");
char name[1000];
char num[1000]; //number[1000]
while (fgets(name, MAX_NAME, stdin) != NULL && fgets(num, MAX_NUM, stdin) != NULL)
{
// copy to struct
strcpy(contacts[contacts_count].name, name);
strcpy(contacts[contacts_count].num, num);
contacts_count++;
}
for (int i = 0; i < contacts_count; i++){
int matchesName = matches(contacts[contacts_count].name, key);
int matchesNumber = matches(contacts[contacts_count].num, key);
if (matchesName || matchesNumber)
printf("%s%s\n", contacts[contacts_count].name, contacts[contacts_count].num);
}
//fclose(f);
return 0;
}
I want to ask the help of experienced programmers.
matchTable[10][9] is too small to save "7pqrsPQRS" as a string as needed in matchTable[j][i] != '\0';. Needs 10.
Suggest
//static char matchTable[10][9] = {
// "0+", "1", "2abcABC", "3defDEF", "4ghiGHI",
// "5jklJKL", "6mnoMNO", "7pqrsPQRS", "8tuvTUV", "9wxyWXY"
//};
static char *matchTable[10] = {
"0+", "1", "2abcABC", "3defDEF", "4ghiGHI",
"5jklJKL", "6mnoMNO", "7pqrsPQRS", "8tuvTUV", "9wxyWXY"
};
Perhaps other issues too.
I believe the main issue is the the search logic. Code loops over all contacts, but will attempt a match against the a non-existing contacts entry.
for (int i = 0; i < contacts_count; i++){
int matchesName = matches(contacts[contacts_count].name, key);
int matchesNumber = matches(contacts[contacts_count].num, key);
...
Should this use the i-th contacts ?
for (int i = 0; i < contacts_count; i++){
int matchesName = matches(contacts[i].name, key);
int matchesNumber = matches(contacts[i].num, key);
if (matchesName || matchesNumber)
printf("%s%s\n", contacts[i].name, contacts[contacts_count].num);
}
Or even
for (int i = 0; i < contacts_count; i++){
struct Folio con_p = &contacts[i] ;
int matchesName = matches(con_p->name, key);
int matchesNumber = matches(con_p->num, key);
if (matchesName || matchesNumber)
printf("%s%s\n", con_p->name, con_p->num);
}
Also take a look at answer from chux - Reinstate Monica

How to divide a string to substring and assign another substring?

I want to divide *eString to substrings. Substrings should be like that:
y_{1} = y_{1}y_{m+1}y_{2m+1}...
y_{2} = y_{2}y_{m+2}y_{2m+2}...
y_{m} = y_{m}y_{2m}y_{3m}...
where y is the element of *eString, and y is the substring of these elements.
For instance, if an user expects the key length which is 5, there should be (string size / 5) substrings. y_{1} has to contain the fist element of each divided substring. So, how can I implement this?
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define ALPHA 26
char *ReadFile(char *);
int main(int argc, char *argv[])
{
double frequency[ALPHA] = {0};
int c = 0;
int keylen = 0;
int counter = 0;
double indexofCoincidence = 0,total = 0;
const char *eString = ReadFile("cipher.txt");
int len = 0;
if (eString) {
puts("The encrypted text is:");
puts(eString);
puts("");
len = strlen(eString);
printf("The length of text is %d\n",len);
}
puts("");
while(eString[c]!= '\0'){
if(eString[c]>= 'a' && eString[c]<='z')
frequency[eString[c]-'a']++;
c++;
}
puts("The letters frequencies are :\n");
for(c=0; c<ALPHA;c++){
if(frequency[c]!= 0)
printf("%c : %.3f\t",c+'a',(frequency[c]/len));
total += (frequency[c]*(frequency[c]-1));
}
indexofCoincidence = (total/((len)*(len-1)));
printf("\n\nIndex of Coincidence : %.3f\n",indexofCoincidence);
if(indexofCoincidence < 0.060){
printf("\nIt looks like randomly.\n");
}
printf("Enter the your expected key length : ");
scanf("%d",keylen);
printf("\n");
char *y;
while(counter != keylen)
{
for(int i = 0; i<(len/keylen);i++){
y[counter] = *eString();
}
counter++
}
return EXIT_SUCCESS;
}
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(void){
char *eString = "The quick brown fox jumps over the lazy dog";
int keylen = 5;
int len = strlen(eString);
int y_len = (len + keylen) / keylen + 1;
int i,j;
char **y = malloc(keylen * sizeof(*y));
for(i=0; i < keylen; ++i){
y[i] = malloc(y_len * sizeof(**y));
}
char *p = eString;
i = j = 0;
while(*p){
y[i % keylen][j] = *p++;
y[i % keylen][j+1] = 0;
if(++i % keylen == 0)
++j;
}
//check print & deallocate
for(i = 0; i < keylen; ++i){
printf("y_{%d} : %s\n", i+1, y[i]);
free(y[i]);
}
free(y);
return 0;
}

Reversing array logic in C not working properly

I am trying to read the input to my program (a string of chars) and invert the order of the words that are in it.
For example, if I were to pass my program ABC DEF GHI JKL it would output JKL GHI DEF ABC. I am using the whitespace as separators.
My code:
char toReverse[1000];
char outputArray[1000];
int charCount = //Size of the toReverse array. Varies on the input
//It is the total number of chars stored in the array
...
int i;
int tempCharCount = charCount;
int wordSize = 0;
int outputIndex = 0;
int sentenceIndex = 0;
int charStep = 0;
for(i = charCount-1; i>=0; i--){
if(toReverse[i] == ' '){
int j;
sentenceIndex = tempCharCount - wordSize;
for(j = 0; j<charStep; j++){
outputArray[outputIndex++] = toReverse[sentenceIndex++];
}
outputArray[outputIndex] = ' ';
outputIndex++;
charStep = 0;
}
wordSize++;
charStep++;
}
There is a flaw in my code. I do know why this happens though. For example, if I were to pass as input ABC DEF GHI, it will only output GHI DEF. This is because whenever the outer for loop reaches index 0 of my toReverse array, since it is not a space ' ', it does not do the if(toReverse[i]) inner for(j = 0; j<charStep; j++) since the condition is not met.
Do you have any advice regarding to the logic? I have tried reversing my logic, such as if(toReverse[i] != ' ') but it brings more problems than it solves.
Thanks for your advice and comments!
Cheers
Edit 1
I am reading my input from a file By the way!
Update 1
Here I am basically trying to open various files and read chars from them
int main(int argc, char * argv[])
{
int i = 1;
FILE * fp = NULL;
if(1==argc){
do_read(stdin);
}else{
// cycle through all files in command line arguments and read them
for (i=1; i < argc; i++) {
if ((fp = fopen(argv[i], "r")) == NULL) {
printf("Failed to open file.\n");
}
else {
do_read(fp);
fclose(fp);
}
}
}
//printf("\n");
//printf("\n");
printf("%i",charCount);
return 0;
}
sample
#include <stdio.h>
#include <string.h>
void proc_rev(char toReverse[], char outputArray[]){
int charCount = strlen(toReverse);
int i;
int tempCharCount = charCount;
int wordSize = 0;
int outputIndex = 0;
int sentenceIndex = 0;
int charStep = 0;
for(i = charCount-1; i>=0; i--){
if(toReverse[i] == ' '){
int j;
sentenceIndex = tempCharCount - wordSize;
for(j = 0; j<charStep; j++){
outputArray[outputIndex++] = toReverse[sentenceIndex++];
}
outputArray[outputIndex] = ' ';
outputIndex++;
charStep = 0;
}
wordSize++;
charStep++;
}
outputArray[outputIndex] = '\0';
}
int main(void){
FILE *fp = stdin;
char toReverse[1000] = " ";
char outputArray[1000];
while(1 == fscanf(fp, "%998[^\n]%*c", &toReverse[1])){
proc_rev(toReverse, outputArray);
puts(outputArray);
}
return 0;
}
void do_read(FILE *fp){
char toReverse[1000] = " ";
char outputArray[1000];
while(1 == fscanf(fp, "%998[^\n]%*c", &toReverse[1])){
proc_rev(toReverse, outputArray);
puts(outputArray);
}
}
This code is not tested but basic idea is reversing the whole string once and then reverse it word by word. idea is correct, implementation may have bugs
void swap(char* s, int i, int j) {
char tmp = s[i];
s[i] = s[j];
s[j] = tmp;
}
void rev(char* stirng, int start, int len) {
for (int i=0; i<len/2; ++i) {
swap(string, i, len-i-1);
}
}
int main() {
char* string = read from file
int len = strlen(string);
rev(string, 0, len);
for (int i=0; i<len;) {
int l = 0;
int j=i;
while (j<len && string[j]!=' ') ++j;
rev(string, i, j-i);
i=j+1;
}
}
The current logic reverses individual words from last to second word. However to reverse the first word you will have to add a check apart from
if(toReverse[i] == ' ')
as the first character need not be a space.
A separate check can be used when counter 'i' reaches zero, i.e. first character

Caesar Cipher not returning correct key

So my decrypter program seems to not be able to find the key and implement it by itself. I noticed that if I changed the key to equal -5 which is the correct key it would print out the decrypted text correctly. However I am unable to figure out how to make the program figure it out by itself without having me to put it in manually. Any help would be greatly appreciated! Thank you!
rotUtils.h
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include "rotUtils.h"
int rotate(int c, int n){
if (n == 0) return c;
int nRot = abs(n) % (RANGECHAR + 1);
if(n > 0)
return rotatePlus(c + nRot);
else
return rotateMinus(c - nRot);
}
int rotatePlus(int sum){
int diff = sum - MAXCHAR;
if (sum > MAXCHAR) sum = MINCHAR + diff - 1;
return sum;
}
int rotateMinus(int sum){
int diff = MINCHAR - sum;
if (sum < MINCHAR) sum = MAXCHAR - diff + 1;
return sum;
}
decrypt.cpp
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include "rotUtils.h"
bool solved( char decodearr[], char dictarr[][30], int size1, int size2){
char* compared;
bool result = false;
for(int j = 0; j < size2; j++){
compared = strstr( decodearr, dictarr[j]);
}
if( compared != '\0'){
result = true;
}
return result;
}
int decode( char codearr[], char dictarr[][30], int size1, int size2)
{
bool solution = false;
int key = -50; This is where I had to change it to -5 to solve
char decodearr[10000];
while(solution == false && key < 51)
{
for( int i = 0; i < size1; i++)
{
if(!isspace(codearr[i]))
{
decodearr[i] = rotate(codearr[i], key);
}
else
decodearr[i] = codearr[i];
}
solution = solved( decodearr, dictarr, size1, size2);
if( solution == false)
{
key++;
}
}
for( int j = 0; j < size1; j++)
{
codearr[j] = decodearr[j];
}
return key;
}
int main( int argc, char* argv[])
{
char* file = argv[1];
char* dictionary = argv[2];
char code[10000];
char dict[30000][30];
FILE* codeFile;
codeFile = fopen(file, "r");
int i = 0;
int j = 0;
int key;
FILE* dictFile;
dictFile = fopen(dictionary, "r");
while(!feof(codeFile))
{
code[i] = fgetc(codeFile);
i++;
}
code[ i ]= '\0';
fclose(codeFile);
while(!feof(dictFile))
{
fscanf(dictFile, "%s", dict[j]);
j++;
}
key = decode(code, dict, i, j);
fclose(dictFile);
for(int k = 0; k < i; k++)
{
printf("%c", code[k]);
}
printf( "\nThe key is: %d\n", key);
return 0;
}
Solved() will only return true if there is a match on the last dictionary word currently, you have to move that check inside. You could print to screen whenever you find a key that has a match on your dictionary and/or keep a list of possible keys then print after you are done with them all, right now you would exit as soon as you find any match even if it was just luck.

How to write a getline function in C?

I know that getline is C++ standard but I need to read a line of digits:
123856
and save it to an array. But how to do this without spaces between given (as input) digits? I want a user input to be:
123856 (with no spaces) and then save it to an array (n element array) and after that, I want my array to look like this:
array[0] = 1;
array[1] = 2;
array[2] = 3;
array[3] = 8;
array[4] = 5;
array[5] = 6;
But how to make it in C, without a getline?
This is NOT what I want:
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <stdbool.h>
int main(int argc, char **argv)
{
int t[4];
int i;
for(i=0; i<4; i++)
scanf("%d", &t[i]);
for(i=0; i<4; i++)
printf("%d\n", t[i]);
return 0;
}
If I understood you correct, the following should do it:
read the whole line
loop through the string as long as you get digits or the string ends
for every digit, place it's value in your array and increase the index by 1
while( ( c = getchar()) != EOF && c != '\n' && i < max ) {
/* If desired, add check for value outside of 0-9 */
array[ i++ ] = c - '0';
...
}
char arr[] = "1234567";
int intarr[10];
int count = 0;
for (char* ptr = arr; *ptr; ptr++) {
intarr[count] = *ptr - '0';
count++;
}
try this
#include <stdio.h>
#include <string.h>
main (int argc, char *argv[])
{
FILE *f;
int i=0;
int j=0;
char output[100];
char* output1[100];
char string[100];
char delims1[] = " ";
char delims2[] = "*";
char* result = NULL;
char* result3 = NULL;
int num;
//for (j=0; j<2; j++)
//{
//printf("%s",delims9[6]);
//}
f = fopen("text.txt","r");
//
while( fgets(string,sizeof(string),f) )
{
result = strtok( string, delims1 );
while( result != NULL )
{
output1[i]=result;
printf("%s\n",output1[i]);
result = strtok( NULL, delims1 );
i++;
}
for (num = 0; num < 100; i++ ) //
{ // Error On this array
printf("%s\n", output1[i]); //
} //
}
printf("\n%d",i/3+1);
return 0 ;
}
Ok, without using any string.
int digits = 123856;
int numofdigits = 1 + floor(log10(digits));
int digits_arr[numofdigits];
int i;
for(i = numofdigits-1; i >= 0; i--) {
digits_arr[i] = (int)floor(digits / pow(10, i)) % 10;
}
Try the below link... Same question asked here and get solution....
convert an integer number into an array
char * convertNumberIntoArray(unsigned int number) {
unsigned int length = (int)(log10((float)number)) + 1;
char * arr = (char *) malloc(length * sizeof(char)), * curr = arr;
do {
*curr++ = number % 10;
number /= 10;
} while (number != 0);
return arr;
}

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