I have to prevent from putting letters into scanf in my program. I tried "isalpha" but is doesn't seems to work. Here is my code:
int main()
{
float T[100] = {0};
float *pt=T;
float suma = 0, zmienna;
int rozmiar;
printf("How many numbers would you like to put in: ");
scanf("%d", &rozmiar);
if (isalpha((char)rozmiar) != 0)
{
printf("Incorrect input");
return 1;
}
else if(rozmiar>100)
{
printf("Incorrect input data");
return 2;
}
else
printf("\n Enter the number: \n");
for (int i = 0; i<rozmiar; i++)
{
scanf("%f", &zmienna);
*(pt+i)=zmienna;
}
}
Related
After running the next code, in the function get_data(), everything runs normally until I get to the end of the For, when program should call the function continue_function() but in somehow, ignores it, and the program just ends.
Am I calling it in a wrong way?
I'm just start learning programming in C and this is one of the last exam's exercises.
#include <stdio.h>
#define MAX 100
#define YES 1
#define NO 0
struct record
{
char fname[15+1];
char lname[20+1];
char phone[9+1];
long income;
int month;
int day;
int year;
};
struct record list[MAX];
int last_entry = 0;
void get_data(void);
void display_report(void);
int continue_function(void);
void clear_kb(void);
main()
{
int cont = YES;
int ch;
while(cont == YES)
{
printf("\n");
printf("\n MENU");
printf("\n =========\n");
printf("\n1. Enter Names");
printf("\n2. Print Report");
printf("\n3. Quit");
printf("\n\nEnter Selection ==> ");
scanf("%d", &ch);
clear_kb();
system("cls");
switch(ch)
{
case 1: get_data();
break;
case 2: display_report();
break;
case 3: printf("\n\nThank You for using this Program!");
cont = NO;
break;
default: printf("\n\nInvalid Choice, Please Select 1 to 3!");
break;
}
}
}
void get_data(void)
{
int cont;
int ctr;
for(cont = YES; last_entry < MAX && cont == YES; last_entry++)
{
printf("\n\nEnter information for Person %d.", last_entry+1);
printf("\n\nEnter first name: ");
gets(list[last_entry].fname);
printf("Enter last name: ");
gets(list[last_entry].lname);
printf("Enter phone in 123-4567 format: ");
gets(list[last_entry].phone);
printf("Enter Yearly Income: ");
scanf("%ld", &list[last_entry].income);
printf("Enter Birthday: ");
do
{
printf("\n\tMonth (0 - 12): ");
scanf("%d", &list[last_entry].month);
}
while (list[last_entry].month < 0 || list[last_entry].month > 12);
do
{
printf("\tDay (0 - 31): ");
scanf("%d", &list[last_entry].day);
}
while (list[last_entry].day < 0 || list[last_entry].day > 31);
do
{
printf("\tYear (1800 - 2025): ");
scanf("%d", list[last_entry].year);
}
while (list[last_entry].year < 1800 || list[last_entry].year > 2025);
cont = continue_function();
}
if(last_entry == MAX)
{
printf("\n\nMaximum Number of Names has been entered!\n");
}
}
void display_report(void)
{
long month_total = 0, grand_total = 0;
int x, y;
fprintf(stdout, "\n\n");
fprintf(stdout, "\n REPORT");
fprintf(stdout, "\n ========");
for(x = 0; x <= 12; x++)
{
month_total = 0;
for(y = 0; y < last_entry; y++)
{
if(list[y].month == x)
{
fprintf(stdout, "\n\t%s %s %s %ld", list[y].fname, list[y].lname, list[y].phone, list[y].income);
month_total += list[y].income;
}
}
fprintf(stdout, "\nTotal for month %d is %ld:", x, month_total);
grand_total += month_total;
}
fprintf(stdout, "\n\nReport Totals:");
fprintf(stdout, "\nTotal Income is %ld", grand_total);
fprintf(stdout, "\nAverage Income is %ld", grand_total/last_entry);
fprintf(stdout, "\n\n* * * End of Report * * *");
}
int continue_function(void)
{
char ch;
printf("\n\nDo you wish to continue? (Y)es/(N)o: ");
getc(ch);
while(ch != 'n' && ch != 'N' && ch != 'y' && ch != 'Y')
{
printf("\n%c is invalid!", ch);
printf("\n\nPlease enter \'N\' to Quit or \'Y\' to Continue: ");
getc(ch);
}
clear_kb();
if(ch == 'n' || ch == 'N')
{
system("cls");
return(NO);
}
else
{
system("cls");
return(YES);
}
}
void clear_kb(void)
{
char junk[80];
gets(junk);
}
You're not using your get functions properly:
https://www.tutorialspoint.com/c_standard_library/c_function_getc.htm
int getc(FILE *); for instance requires a FILE* as argument and returns the character, but you are passing the character as argument, it should look like ch = getc(stdin);.
On another note, notice that when you use scanf you pass &c? This is because for a value to be modified, you need to pass the address where it's stored (&) and not the value itself. So even if getc took a char, it would have to be getc(&ch).
You should follow a quick tutorial on pointers and types, if you come from a higher level language or if you're new that could be a good idea.
When the "do you wish to quit" question/main function is asked an answered with 'n' I need the code to then ask the question again and again until the user is done with the program. Aka repeating for as ever long as necessary
int getNumTerms()
{
int n;
printf("Enter the number of terms: \n");
scanf("%d",&n);
return n;
}
double coshyper (double x, int n)
{
int i;
double sum=1, term=1;
for (i=1; i<n; i++)
{
term=(x*x/(2.0*(double)i*(2.0*(double)i-1.0)))*term;
sum=sum+term;
}
return sum;
}
int main()
{
char q;
printf("Do you wish to quit(y/n)?\n");
scanf("%c",&q);
if(q=='y')
{
printf("Program Terminated\n");
}
while(q=='n')
{
int n;
double x;
printf("Enter x: \n");
scanf("%lf",&x);
n=getNumTerms();
double result = coshyper(x,n);
printf("The value for cosh(%.3lf) for %d terms is %.6lf\n",x,n,result);
}
}
You can change the main to something like this:
int main()
{
char q = 'n';
do{
if(q == 'y'){
printf("Program Terminated\n");
break;
}
if(q == 'n'){
int n;
double x;
printf("Enter x: \n");
scanf("%lf",&x);
n=getNumTerms();
double result = coshyper(x,n);
printf("The value for cosh(%.3lf) for %d terms is %.6lf\n",x,n,result);
}
else
{
printf("Invalid");
}
printf("Do you wish to quit(y/n)?\n");
scanf("%c",&q);
}while(1);
return 0;
}
I need to make a program that stores numbers inside of an array. But it must have no duplicate elements.
int x;
int z[8];
for( x = 0; x<8;x++)
printf("number: ");
scanf("%d",&z[x]);
}
for( x=0;x<8;x++) {
printf("%d ",z[x]);
}
First, initialize the array, so that you do not end up reading an uninitialized value and fail the test.
int user_nums[6] = {0};
Next, you need to have another check in the for loop, to read the number again if it is a duplicate.
The code will look like this.
#include<stdio.h>
int main(){
int x,y;
int exists = 0;
int user_nums[6] = {0};
for( x = 0; x<6;x++){//for loop to get the players selected numbers
do {
exists = 0;
printf("Enter a number(from the #'s 1-42): ");
scanf("%d",&user_nums[x]);
for(y =0; y < x; y++) { //to check for duplicates
if (user_nums[x] == user_nums[y])
{
printf("Number already exists\n ");
exists = 1;
break;
}
}
}while (user_nums[x]<1 || user_nums[x]>42 || exists);//accepts only numbers from 1-42 which are not duplicates (continous to ask you for a number until condition is met).
}
printf("Your numbers: \n");
for( x=0;x<6;x++){
printf("%d ",user_nums[x]); // prints the numbers you inputed.
}
return 0;
}
The following code could work in O(n):
#include<stdio.h>
int main()
{
int user_nums[6];
int index[50];
for (int i = 0; i != sizeof(index) / sizeof(index[0]); ++i)
index[i] = -1;
for (int i = 0; i < sizeof(user_nums) / sizeof(user_nums[0]); ++i) {
for (;;) {
printf("Enter a number(from the #'s 1-42): ");
scanf("%d", user_nums + i);
if (user_nums[i] < 1 || user_nums[i] > 42) {
printf("wrong number\n");
continue;
}
if (index[user_nums[i]] != -1) {
printf("dump number\n");
continue;
}
index[user_nums[i]] = i;
break;
}
}
printf("Your numbers: \n");
for(int i = 0; i < 6; ++i)
printf("%d ", user_nums[i]);
return 0;
}
So, I managed to wrangle some code to get part of my program working. My program has to have a prompt to enter grades (done), repeat in a loop until broken (doneish), and print results of each grade entered. The last part is where I am stuck. I can't seem to find a good way to get any grade I entered to print at the end. I just want a "you entered ###, ###, ###," or something similar, but it can be up to 100 numbers. Below is what I have so far
#include <stdio.h>
#define MAX_ARRAY_SIZE 100
int main(void) {
int grade[MAX_ARRAY_SIZE];
int entryCount = 0;
char continueResponse;
printf("Enter an grade of between 1 and 100. \n");
printf("Enter a maximum of %d grades. \n", MAX_ARRAY_SIZE);
int i;
for(i = 0; i < MAX_ARRAY_SIZE; i++) {
printf("Enter grade: ");
scanf("%d", &grade[i]);
printf("Continue? (y/n): ");
scanf(" %c", &continueResponse);
entryCount++;
if(continueResponse == 'n' || continueResponse == 'N') {
printf(" == End of Data Entry ==\n\n");
break;
}
}
return 0;
}
Keep in mind this is third week of doing this, so I know next to nothing. If there's a "why did you do this like this", the answer is because that's how I've done it before and it works. I appreciate any input!
After your dataentry loop:
for(i = 0; i < MAX_ARRAY_SIZE; i++) {
...
}
You just have to add a second loop:
for(i = 0; i < entryCount; i++) {
printf ("%d ", grade[i]);
}
You've recorded entryCount entries to the array, numbered 0 ... entryCount - 1; you'd use another for loop to print them. For nicer formatting we do not print ", " after the last number:
printf("You've entered ");
for (i = 0; i < entryCount; i++) {
if (i == entryCount - 1) {
printf("%d", grade[i]);
}
else {
printf("%d, ", grade[i]);
}
}
printf("\n");
what I understood about your problem the following code would work:
#include <stdio.h>
#define MAX_ARRAY_SIZE 100
int main(void) {
int grade[MAX_ARRAY_SIZE];
int entryCount = 0;
char continueResponse;
printf("Enter an grade of between 1 and 100. \n");
printf("Enter a maximum of %d grades. \n", MAX_ARRAY_SIZE);
int i;
for(i = 0; i < MAX_ARRAY_SIZE; i++) {
printf("Enter grade: ");
scanf("%d", &grade[i]);
printf("Continue? (y/n): ");
scanf(" %c", &continueResponse);
entryCount++;
printf("you entred:\n");
for(int j=0;j<entryCount;j++)
{
printf("%d ",grade[j]);
}
if(continueResponse == 'n' || continueResponse == 'N') {
printf(" == End of Data Entry ==\n\n");
break;
}
}
return 0;
}
No matter how I edit my program there seems to be overflow errors and mismatching type errors. Can someone help me to make this run without errors.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main() {
int choice;
int i;
int j;
char type;
int amount;
int don_count = 0;
int req_count = 0;
int flag;
char donations_inv_type[100][20];
int donations_amount[100];
char requests_inv_type[100][20];
int req_amount[100];
printf("Welcome to the Food Bank Program\n\n 1. Add a donation\n 2. Add a request\n 3. Fulfill a request\n 4. Print status report\n 5. Exit\n\nEnter your choice: ");
scanf("%d", &choice);
while (choice != 5) {
if (choice == 1) {
printf("\nEnter inventory type: ");
scanf("%s", &type);
printf("Enter the amount: ");
scanf("%d", &amount);
printf("\nDonation Added!\n\n");
flag = -99;
for (i = 0; i < don_count; i++) {
if (strcmp(donations_inv_type[i], type) == 0)
flag = i;
}
if (flag == -99) {
strcpy(donations_inv_type[i], type);
donations_amount[i] = amount;
don_count++;
}
else
donations_amount[flag] += amount;
printf("Donation Added!\n");
printf("Press any key to continue . . .\n\n");
}
else if (choice == 2) {
printf("\nEnter inventory type: ");
scanf("%s", &type);
printf("Enter the amount: ");
scanf("%d", &amount);
strcpy(requests_inv_type[req_count], type);
req_amount[req_count] = amount;
req_count++;
}
else if (choice == 3) {
printf("\n\n-------- Fulfilling Requests--------");
flag = -99;
for (i = 0; i < don_count; i++) {
if (strcmp(donations_inv_type[i], requests_inv_type[0]) == 0)
flag = i;
}
if (flag == -99)
printf("Cannot be Fulfilled\n\n");
else if (donations_amount[flag] > req_amount[0]) {
donations_amount[flag] -= req_amount[0];
printf("Request Fulfilled");
req_amount[0] = 0;
}
else if (donations_amount[flag] == req_amount[0]) {
printf("Request Fulfilled");
for (i = flag; i < don_count; i++) {
strcpy(donations_inv_type[i], donations_inv_type[i + 1]);
strcpy(donations_amount[i], donations_amount[i + 1]);
}
don_count--;
for (i = flag; i < req_count; i++) {
strcpy(requests_inv_type[i], requests_inv_type[i + 1]);
strcpy(req_amount[i], req_amount[i + 1]);
}
req_count--;
}
else if (donations_amount[flag] < req_amount[0]) {
printf("Partially Fulfilled");
req_amount[0] -= donations_amount[flag];
for (i = flag; i < don_count; i++) {
strcpy(donations_inv_type[i], donations_inv_type[i + 1]);
strcpy(donations_amount[i], donations_amount[i + 1]);
don_count--;
}
}
}
else if (choice == 4) {
printf("Printing the Donations Table\n\n");
for (i = 0; i < don_count; i++) {
printf("%s %d", donations_inv_type[i], donations_amount[i]);
}
printf("Printing the Requests Table\n\n");
for (i = 0; i < req_count; i++) {
printf("%s %d", requests_inv_type[i], req_amount[i]);
}
}
printf("Welcome to the Food Bank Program\n\n 1. Add a donation\n 2. Add a request\n 3. Fulfill a request\n 4. Print status report\n 5. Exit\n\nEnter your choice: ");
}
}
Any help is greatly appreciated and I would love an explanation as to what I did wrong so that I can learn and not make the same mistakes next time.
Declare type as character array.
char type[50];
Remove & in scanf(). You should not use & while reading string.
scanf("%s", &type); ==> scanf("%s", type);
^
Here you want to copy integers not strings
strcpy(donations_amount[i], donations_amount[i + 1]);
strcpy(req_amount[i], req_amount[i + 1]);
Modify like this
donations_amount[i]=donations_amount[i + 1];
req_amount[i]= req_amount[i + 1];
Instead of char type you need char type[100]
Error in your code:
if (strcmp(donations_inv_type[i], type) == 0)
// ^^^^ should be char*
Note: Functions strcmp() and strcpy() should be passed \0 nul-terminated array of char (or say string).
Your scanf should look like scanf("%s", type);