/in/foo.cc: In function 'int main()':
/in/foo.cc:13:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=1;i<=n;i++) cin>>a[i];
              ~^~~
/in/foo.cc:14:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=1;i<=m;i++){
              ~^~~
/in/foo.cc:16:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   if(t>p) for(p++;p<=t;p++) insert(a[p]); p--;
   ^~
/in/foo.cc:16:43: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
   if(t>p) for(p++;p<=t;p++) insert(a[p]); p--;
                                           ^