Compilare: user.cpp: In function ‘int main()’: user.cpp:101:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v.size(); ++i) { ^ user.cpp:58:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nustiu.in", "r", stdin); ^ user.cpp:59:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nustiu.out", "w", stdout); ^ user.cpp:62:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &tests); ^ user.cpp:66:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:74:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ user.cpp: In function ‘int bfs(int)’: user.cpp:50:12: warning: ‘ans’ may be used uninitialized in this function [-Wmaybe-uninitialized] return ans; ^