Is my do while loop not working due to this function? - c

Question

Im making a program where it asks the user to guess a number 1-100 that the computer is thinking about.
In the end of the program, when the user has guessed the correct number, im trying to get the program to ask if user wants to play again (restart the program).
To solve this, i tried using a do while loop & char repeat;. The loop is stretching from almost the beginning of the program, until the end, althought without success. Does anyone know what im doing wrong? Is it because of the function talfunktion, that the loop won't pass?
Code:
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int talfunktion (int tal, int guess, int tries, char repeat);
int main () {
do {
srand(time(NULL));
int tal = rand() % 100 + 1; //tal is the correct value that the code is thinking of
int guess; //guess is the guessed value of the user
int tries = 0; // amount of tries it took until getting correct
char repeat;
printf("Psst, the right number is: %d \n", tal); // remove later, not relevant to uppg.
printf("Im thinking of a number between 1 and 100, guess which!");
printf("\nEnter: ");
scanf("%d", &guess);
guess = talfunktion(tal, guess, tries, repeat);
getchar();
getchar();
return 0;
}
int talfunktion(int tal, int guess, int tries, char repeat) {
do {
if (guess < tal) {
tries++;
printf("\nYour guess is too low, try again!");
printf("\nEnter: ");
scanf("%d", &guess);
}
else if (guess > tal) {
tries++;
printf("\nYour guess is too high, try again!");
printf("\nEnter: ");
scanf("%d", &guess);
}
} while (guess > tal || guess < tal);
if (guess == tal) {
printf("\nCongratulations, that is correct!");
tries++;
printf("\nYou made %d attempt(s)", tries);
printf("\nPlay Again? (y/n)");
scanf("%c", &repeat);
}
} while (repeat == 'y' || repeat == 'Y');
}

Answer 1

This is one possible solution
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
void talfunktion(int tal, int guess, int* tries)
{
if (guess < tal)
{
(*tries)++;
printf("\nYour guess is too low, try again!");
}
else if (guess > tal)
{
(*tries)++;
printf("\nYour guess is too high, try again!");
}
else if (guess == tal)
{
(*tries)++;
printf("\nCongratulations, that is correct!");
printf("\nYou made %d attempt(s)", *tries);
}
}
int main (void)
{
int tal; //tal is the correct value that the code is thinking of
int guess; //guess is the guessed value of the user
int tries = 0; // amount of tries it took until getting correct
char playAgain;
do {
srand(time(NULL));
tal = rand() % 100 + 1; //tal is the correct value that the code is thinking of
printf("\nIm thinking of a number between 1 and 100, guess which!");
printf("\nEnter: ");
scanf("%d", &guess);
talfunktion(tal, guess, &tries);
printf("\nPsst, the right number is: %d", tal); // remove later, not relevant to uppg.
getchar(); //to halt the code for taking the input
if(guess == tal)
{
tries = 0;
printf("\nPlay Again? (y/n)\n");
scanf("%c", &playAgain);
}
} while (playAgain != 'n');
return 0;
}

Answer 2

There are several things mentioned in the comments that describe problems,
Things you should look at:
Do not define a function inside another function
be careful where you place return statements
when using character testing, use char type for variable
consider simplifying your logical comparisons. (eg guess > tal || guess < tal is the same as guess != tal )
make sure automatic variables are placed such that they are visible where used.
Place space in format specifier: " %c" for scanf() to consume newline character. (instead of excessive use of getchar())
Here is a simplified version of your code, with modified main and talfunktion functions...
char talfunktion(int tal);
int main (void) {
int tal=0;//remove from inside {...} to make it visible to rest of function
char repeat = 'n';
srand(time(NULL));
tal = rand() % 100 + 1; //tal is the correct value that the code is thinking of
do {
repeat = talfunktion(tal);
}while((tolower(repeat) == 'y'));
return 0;
}
char talfunktion(int tal)//do all relevant work in function and return
{ //only what is necessary
int guess = 0;
char repeat = 'n';
printf("Im thinking of a number between 1 and 100, guess which!");
printf("\nEnter a number from 1 to 100: ");
scanf("%d", &guess);
if((guess < 1) || (guess > 100))
{
printf("Entered out of bounds guess...\n");
}
else if (guess != tal)
{
if(guess < tal) printf("guess too small\n");
else printf("guess too large\n");
printf("Try again? <'n' or 'y'>\n");
scanf(" %c", &repeat);//space in format specifier to consume newline character
if(tolower(repeat) != 'y') return 'n';//tolower() allows both upper and lower case
}
else
{
printf("Congratulations: You guessed right.\n");
printf("Play again? <'n' or 'y'>\n");
scanf(" %c", &repeat);
}
return repeat;
}