Compilare: user.cpp: In function ‘void solve(int, int)’: user.cpp:27:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < adj[nod].size(); i++) ^ user.cpp:49:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < adj[nod].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:78:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("plopi.in", "r", stdin); ^ user.cpp:79:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("plopi.out", "w", stdout); ^ user.cpp:82:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:85:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &a, &b, &c); ^