Compilare: main.cpp: In function 'int main()': main.cpp:54:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<v[x].size(); i++) ~^~~~~~~~~~~~ main.cpp:28:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("catun.in","r",stdin); ^ main.cpp:29:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("catun.out","w",stdout); ^ main.cpp:30:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&n,&m,&k); ^ main.cpp:35:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x); ^ main.cpp:43:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&x,&y,&c); ^