Compilare: main.cpp: In function 'int main()': main.cpp:37:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<g[i].size();j++) ~^~~~~~~~~~~~ main.cpp:15:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("sortaret.in", "r", stdin); ^ main.cpp:16:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("sortaret.out", "w", stdout); ^ main.cpp:19:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ main.cpp:23:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^