1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 | #include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>
//#define times_5(n) n + 5 // WRONG
//#define times_5(n) (n * 5) // BETTER, but still WRONG
#define times_5(n) ((n) * 5) // GOOD ★
int main(int argc, char* argv[]) {
int n = times_5(5 + 100); // expect 525
// After preprocessor, this line ↑ turns to this:
// int n = ((5 + 100) * 5)
// … so we will have n == 525 which is correct
printf("n == %d\n", n);
return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */
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