Compilare: main.cpp: In function 'int main()': main.cpp:45:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1 ; i < v.size() ; i++) ~~^~~~~~~~~~ main.cpp:31:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("reactivi.in","r",stdin); ^ main.cpp:32:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("reactivi.out","w",stdout); ^ main.cpp:34:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ main.cpp:38:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^