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#include <bits/stdc++.h>
using namespace std;
long long a[1005],n,q,l,r,k[1005];
bool flag;
int main()
{
    cin >> n >> q;
    for (int i = 1;i <= n;i++)
    {
        cin >> a[i];
    }
    for (int i = 1;i <= q;i++)
    {
        flag = true;
        cin >> l >> r;
        if ((r - l) % 2 == 0) 
        {
            cout << "NO" << endl;
            continue;
        }
        for (int p = l;p <= r;p++)
        {
            k[p] = a[p];
        }
        sort(k + l,k + r + 1);
        for (int j = l;j <= r;j += 2)
        {
            if (k[j] != k[j + 1]) flag = false;
        }
        if (flag)
        {
            cout << "YES" << endl;
        }
        else
        {
            cout << "NO" << endl;
        }
    }
}

#include<bits/stdc++.h>
using namespace std;
int n ,t,a[1005],b[1005],ans;
int main()
{
    cin>>n>>t;
    for(int i=1;i<=n;i++)
    {
        cin>>a[i];
    }
    for(int i=1;i<=t;i++)
    {
        for(int j=1;j<=1005;j++)
        {
            b[j]=0;
        }
        int l=0,r=0;
        cin>>l>>r;
        if((r-l+1)%2!=0)
        {
            cout<<"NO"<<endl;
            ans=1;
        }
        for(int j=l;j<=r;j++)
        {
            b[j]=a[j];
        }
        sort(b+l,b+r+1);
        int sum=0;
        for(int j=l;j<=r;j++)
        {
            if(b[j]!=0&&b[j+1]!=0)
            {
                if(b[j]==b[j+1])
                {
                    b[j]=0;
                    b[j+1]=0;
                }
                else
                {
                    sum++;
                }
            }
        }
        if(ans!=1)
        {
            if(sum==0)
            {
                cout<<"YES"<<endl;
            }
            else
            {
                cout<<"NO"<<endl;
            }
        }
    }
    return 0;
}