Compilare: main.cpp: In function 'int main()': main.cpp:201:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<CICLU[1].size(); i++) ~^~~~~~~~~~~~~~~~ main.cpp:204:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i==CICLU[1].size()) ~^~~~~~~~~~~~~~~~~ main.cpp:161:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("links.in", "r", stdin); ^ main.cpp:162:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("links.out", "w", stdout); ^ main.cpp:163:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &N, &M); ^ main.cpp:166:41: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &P[i].F, &P[i].S); ^ main.cpp:189:57: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d", &X[1], &Y[1], &X[2], &Y[2]); ^