Compilare: user.cpp: In function ‘int cmmmc(int, int)’: user.cpp:14:21: warning: suggest parentheses around assignment used as truth value [-Wparentheses] while ( r = a % b ) ^ user.cpp: In function ‘int main()’: user.cpp:23:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("perm2.in" , "r" , stdin ); ^ user.cpp:24:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("perm2.out" , "w" , stdout ); ^ user.cpp:25:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d" , &n ); ^ user.cpp:27:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d " , &v[i]); ^