frequent values

#include <iostream>
#include<climits>
using namespace std;
struct s{
    int l;
    int r; int max; int lv; int rv; int mv;
}tree[500005];
int a[100005];
void build_tree(int n, int l,int r){
    if(l<0||r>100000) return ;
    if(l==r){
        tree[n].r=tree[n].max=tree[n].l=1; tree[n].rv=tree[n].mv=tree[n].lv=a[l]; return ;
    }
    int mid=(l+r)>>1;
     build_tree(2*n+1,l,mid);
     build_tree(2*n+2,mid+1,r);
     if(tree[2*n+1].rv==tree[2*n+2].lv&&tree[2*n+1].lv==tree[2*n+2].rv&&tree[2*n+1].lv==tree[2*n+1].rv){
         tree[n].r=tree[n].max=tree[n].l=r-l+1; tree[n].rv=tree[n].mv=tree[n].lv=a[l];
    }
    else if(tree[2*n+1].rv==tree[2*n+2].lv&&tree[2*n+1].lv==tree[2*n+1].rv){
         tree[n].r=tree[2*n+2].r;
         tree[n].max=tree[n].l=tree[2*n+1].max+tree[2*n+2].l;
         tree[n].rv=tree[2*n+2].rv;
         tree[n].mv=tree[n].lv=tree[2*n+1].lv;
    }
    else if(tree[2*n+1].rv==tree[2*n+2].lv&&tree[2*n+2].lv==tree[2*n+2].rv){
        tree[n].l=tree[2*n+1].l;
         tree[n].max=tree[n].r=tree[2*n+2].max+tree[2*n+1].r;
         tree[n].mv=tree[n].rv=tree[2*n+2].rv;
        tree[n].lv=tree[2*n+1].lv;
    }
     else if(tree[2*n+1].rv==tree[2*n+2].lv){
        tree[n].l=tree[2*n+1].l;
        tree[n].r=tree[2*n+2].r;
        tree[n].max=max(max(tree[2*n+1].max,tree[2*n+2].max),tree[2*n+2].l+tree[2*n+1].r);
        tree[n].rv=tree[2*n+2].rv;
        tree[n].lv=tree[2*n+1].lv;
        if(tree[n].max==tree[2*n+1].max)
        tree[n].mv=tree[2*n+1].mv;
        else if(tree[n].max==tree[2*n+2].max)
        tree[n].mv=tree[2*n+2].mv;
        else tree[n].mv=tree[2*n+1].rv;
    }
    else{
         tree[n].l=tree[2*n+1].l;
        tree[n].r=tree[2*n+2].r;
        tree[n].max=max(tree[2*n+1].max,tree[2*n+2].max);
         tree[n].rv=tree[2*n+2].rv;
        tree[n].lv=tree[2*n+1].lv;
        if(tree[n].max==tree[2*n+1].max)
        tree[n].mv=tree[2*n+1].mv;
        else
        tree[n].mv=tree[2*n+2].mv;

    }
}
s query(int n,int i,int j,int l,int r){ s p,q1,q2;
p.l=p.r=p.max=p.lv=p.rv=p.mv=0;
    if(i>j||l>j||r<i) return p;
    else if(i>=l&&j<=r)
    return tree[n];
    int mid=(i+j)>>1;
    q1=query(2*n+1,i,mid,l,r); q2=query(2*n+2,mid+1,j,l,r);
    if(q1.rv==q2.lv){
        p.max=max(max(q1.max,q2.max),q1.r+q2.l);
        p.l=q1.l; p.r=q2.r;
        p.lv=q1.lv; p.rv=q2.rv;
        if(p.max==q1.max) p.mv=q1.mv;
        else if(p.max==q2.max) p.mv=q2.mv;
        else p.mv=q1.rv;
    }
    else{
        p.max=max(q1.max,q2.max);
        p.l=q1.l; p.r=q2.r;
        p.lv=q1.lv; p.rv=q2.rv;
        if(p.max==q1.max) p.mv=q1.mv;
        else p.mv=q2.mv;
    }
    return p;
}

int main() {
int n,q; cin>>n;
while(n!=0){cin>>q;

  for(int i=0;i<n;i++) cin>>a[i];
  build_tree(0,0,n-1);
  for(int i=0;i<q;i++){
      int l,r; cin>>l>>r; l--; r--;
      s x=query(0,0,n-1,l,r);
      cout<<x.max<<endl;
  }
    cin>>n;
}
return 0;
}