Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:14:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j<a[x].size(); j++) ^ user.cpp: In function ‘int main()’: user.cpp:23:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("srevni.in", "r", stdin); ^ user.cpp:24:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("srevni.out", "w", stdout); ^ user.cpp:26:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:29:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &pret[i]); ^ user.cpp:34:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^