Compilare: user.cpp: In function ‘bool bfs()’: user.cpp:29:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < l[x].size(); i++){ ^ user.cpp: In function ‘void bfs2(int, bool*)’: user.cpp:50:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < l[x].size(); i++){ ^ user.cpp: In function ‘int main()’: user.cpp:74:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < l[n].size(); i++) ^ user.cpp:61:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("critice.in", "r", stdin); ^ user.cpp:62:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("critice.out", "w", stdout); ^ user.cpp:63:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:65:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &x, &y, &z); ^