How to change the output of printf() in main() ?
Consider the following program. Change the program so that the output of printf is always 10. It is not allowed to change main(). Only fun() can be changed.
void fun() { // Add something here so that the printf in main prints 10 } int main() { int i = 10; fun(); i = 20; printf("%d", i); return 0; } |
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We can use Macro Arguments to change the output of printf.
#include <stdio.h> void fun() { #define printf(x, y) printf(x, 10); } int main() { int i = 10; fun(); i = 20; printf("%d", i); return 0; } |
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Output:
10
This article is contributed by Abhay Rathi. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above
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