Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:7:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[nod].size(); i ++) ^ user.cpp:11:37: 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:20:12: warning: unused variable ‘m’ [-Wunused-variable] int n, m, i, a, b; ^ user.cpp:18:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("asmax.in", "r", stdin); ^ user.cpp:19:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("asmax.out", "w", stdout); ^ user.cpp:21:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:23:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &val[i]); ^ user.cpp:25:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a, &b); ^