Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:23:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < g[node].size(); ++ i) ^ user.cpp: In function ‘int main()’: user.cpp:83:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < g[node].size(); ++ j) ^ user.cpp:100:47: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < gt[node].size(); ++ j) ^ user.cpp:111:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < g[node].size(); ++ j) ^ user.cpp:34:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("revolve.in", "r", stdin); ^ user.cpp:35:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("revolve.out", "w", stdout); ^ user.cpp:37:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &t); ^ user.cpp:42:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i %i", &n, &m); ^ user.cpp:45:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i %i %i", &a, &b, &c); ^