Compilare: user.cpp: In function ‘int main()’: user.cpp:49:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bfs2.in", "r", stdin); ^ user.cpp:50:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bfs2.out", "w", stdout); ^ user.cpp:51:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&n,&m,&lim); ^ user.cpp:52:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i=1;i<=n;i++) scanf("%d",&v1[i]); ^ user.cpp:53:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i=1;i<=m;i++) scanf("%d",&v2[i]); ^ user.cpp:57:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(scanf("%d",&q);q;q--) ^ user.cpp:61:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("\n%c %d%d",&c,&x,&y); ^