- #include <stdio.h> 
- #define SUB_UNSAFE(x, y) x * y 
- #define SUB(x, y) ((x) * (y)) 
-   
- int main(void) { 
- 	printf("%d\n",-  SUB_UNSAFE (4 - 4, 2));
 
- 	printf("%d\n",-  SUB (4 - 4, 2));
 
- } 
-   
- //http://pt.stackoverflow.com/q/192041/101 
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