C Programming Code Examples
C > Miscellaneous Code Examples
Macro to substitude values etc
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/* Macro to substitude values etc */
#include <stdio.h>
#define swap(a, b) a ^= b ^= a ^= b;
int main(void) {
char one = 'a', two = 'b';
/* one = a, two = 'b' */
printf("before : %c %c\n", one, two);
swap(one, two);
/* one = 'b', two = a */
printf("after : %c %c\n", one, two);
return 0;
}
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