Compilare: user.cpp: In function ‘void BFS(int)’: user.cpp:13:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < adj[node].size(); i++){ ^ user.cpp:17:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < adj[node].size(); i++){ ^ user.cpp:18:51: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < adj[adj[node][i]].size(); j++){ ^ user.cpp: In function ‘int main()’: user.cpp:29:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("triplete.in", "r", stdin); ^ user.cpp:30:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("triplete.out", "w", stdout); ^ user.cpp:32:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &vertices, &edges); ^ user.cpp:35:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &u, &v); ^