Compilare: user.cpp: In function ‘void BFS()’: user.cpp:54:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[u].size(); ++ i) ^ user.cpp:43:12: warning: unused variable ‘v’ [-Wunused-variable] int u, v, k; ^ user.cpp: In function ‘void read()’: user.cpp:26:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &N, &M, &X); ^ user.cpp:29:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &u, &v); ^ user.cpp:35:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &u); ^