foo.cc: In function 'int main()':
foo.cc:54:6: error: redeclaration of 'int m'
  int m;cin>>m;for(int i=1;i<=m;i++) cin>>query[i].l>>query[i].r,query[i].index=i;
      ^
foo.cc:46:8: note: 'int m' previously declared here
  int n,m;cin>>n>>m;
        ^

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。