K题 求助

#include<bits/stdc++.h>
using namespace std;
#define ll long long
int a[500500];
int pre[500500];
map<int,int> mp;
int main()
{
    int t;
    cin>>t;
    while(t--)
    {
        int n,k;
        mp.clear();
        memset(a,0,sizeof(a));
        memset(pre,0,sizeof(pre));
        scanf("%d%d",&n,&k);
        int ml=0,mr=k;
        int lm=k,rm=0;
        int f=1;
        for(int i=1;i<=n;i++)
        {
            scanf("%d",&a[i]);
            if(mp.find(a[i])!=mp.end())
            {
                pre[i]=mp[a[i]];
            }
            mp[a[i]]=i;
        }
        for(int i=1;i<=n;i++)
        {
            if(a[i]>k)
            {
                cout<<"NO"<<endl;
                f=0;
                break;
            }
            if(pre[i])
            {
                if(pre[i]>i-k)
                {
                    if((pre[i]%k)<(i%k))
                    {
                        ml=max(ml,pre[i]%k);
                        mr=min(mr,i%k);
                    }
                    else
                    {
                        lm=min(lm,i%k);
                        rm=max(rm,pre[i]%k);
                    }
                }
            }
        }
        if(f)
        {
            if(ml<mr&&(ml<lm||mr>rm))
                printf("YES\n");
            else
                printf("NO\n");
        }

    }
}
/*
8 3
2 3 2 1 3 3 2 1
10 3
1 1 2 3 3 2 1 2 3 1
10 3
1 2 1 2 3 3 2 3 1 1
*/