Compilare: user.cpp: In function ‘void bfs()’: user.cpp:40:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<g[1].size(); i++) ^ user.cpp:61:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0; j<g[s].size(); j++) ^ user.cpp: In function ‘int main()’: user.cpp:98:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<sg.size(); i++) ^ user.cpp:77:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.in", "r",stdin); ^ 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("apm.out", "w", stdout); ^ user.cpp:85:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d \n", &x, &y, &z); ^