Compilare: main.cpp: In function 'int main()': main.cpp:35:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0 ; i < G[x].size() ; i ++) ~~^~~~~~~~~~~~~ main.cpp:12:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cezar.in" , "r" , stdin); ^ main.cpp:13:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cezar.out" , "w" , stdout); ^ main.cpp:15:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d" , &n , &k); ^ main.cpp:18:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d" , &x , &y); ^