Compilare: main.cpp: In function 'int main()': main.cpp:12:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cifre4.in", "r", stdin); ^ main.cpp:13:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cifre4.out", "w", stdout); ^ main.cpp:16:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ main.cpp:20:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &p, &n); ^ main.cpp:81:19: warning: iteration 5000000 invokes undefined behavior [-Waggressive-loop-optimizations] vis[i]=false; ~~~~~~^~~~~~ main.cpp:80:22: note: within this loop for(int i=1;i<=nmax;i++) ~^~~~~~