test.c

#include <stdio.h>
#include <ctype.h>
#include <string.h>

void swap (int* num1, int* num2) {

    *num1 = *num1 ^ *num2;
    *num2 = *num1 ^ *num2;
    *num1 = *num1 ^ *num2;
}

int factorial (int n) {
    int res = 0;
    return (res = ((n==0) || (n==1)) ? 1: n * factorial (n-1));
}
 
int main (void) {

    int i = 0;
    int c = 0;

    int a = 10; 
    int b = 20; 
    int *a_ptr;
    char out[200U]; 
    void (*fun_ptr) (int*, int*);

    memset(out, 0, sizeof(out));

    for (i = 1; i <= 100; i++) {
        // if (i%3==0) {
        //     (i%5==0) ? printf("\nFizzBuzz"): printf("\nFizz");
        // } else if (i%5==0) {
        //     printf("\nBuzz");
        // }
        // else printf("\n%d", i);

            (i%3==0)? (i%5==0) ? printf("\nFizzBuzz"): printf("\nFizz") : (i%5==0)? printf("\nBuzz"): printf("\n%d", i);
    }

    printf ("\n Factorial 1 = %d", factorial (1));
    printf ("\n Factorial 2 = %d", factorial (2));
    printf ("\n Factorial 3 = %d", factorial (3));
    printf ("\n Factorial 4 = %d", factorial (4));
    printf ("\n Factorial 5 = %d", factorial (5));

    // while ((c = getchar()) != EOF)
    //     putchar(tolower(c));
    // return 0;

    fun_ptr = &swap;
    
    printf ("%d %d\n", a, b);

    fun_ptr (&a, &b);
    
    printf ("%d %d\n", a, b);

    a_ptr = &a;

    printf("\n%d %d", (*a_ptr)++, (*a_ptr));

    // i = 0;

    // while ((c = getchar()) != EOF) {   
    //     if (c == '\t') {
    //         out[i++] = '\\';
    //         out[i++] = 't';
    //     } 
    //     else {
    //         out[i++] = (char)c;
    //     }
    // }

    // printf ("\nTotal characters: %d", i);
    // printf ("\nFormatted string: %s", out);
}