Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:19:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[nod].size (); ++i) { ^ user.cpp: In function ‘void dfs2(int)’: user.cpp:39:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[nod].size (); ++i) { ^ user.cpp: In function ‘int main()’: user.cpp:73:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < sol.size (); ++i) ^ user.cpp:79:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < sol.size (); ++i) ^ user.cpp:49:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("victorie.in", "r", stdin); ^ user.cpp:50:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("victorie.out", "w", stdout); ^ user.cpp:53:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &n, &m); ^ user.cpp:55:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &x, &y); ^