#include<bits/stdc++.h>
#define int long long
using namespace std;
int num[1000005];
bool vis[1000005];
int n,m,ans1,ans2;
int p1,p2;
int check(int mid)
{
	p1=1,p2=mid;
	for(int i=1;i<=n-mid;i++)
	{
		memset(vis,0,sizeof(vis));
		int cnt=0;
		for(int j=p1;j<=p2;j++)
		{
			if(vis[num[j]]==0)
			{
				vis[num[j]]=1;
				cnt++;
			}
		}
		if(cnt>=m)
			return 1;
		p1++,p2++;
	}
	return 0;
}
signed main()
{
	cin>>n>>m;
	for(int i=1;i<=n;i++) 
		scanf("%d",&num[i]);
	int l=1,r=n+1;
	while(l<r-1)
	{
		int mid=(l+r)/2;
		cout<<mid<<endl;
		if(mid<m)
		{
			l=mid+1;
			continue;
		}
		if(check(mid)==1)
		{
			ans1=p1,ans2=p2;
			r=mid;
		}
		else
			l=mid+1;
	}
	cout<<ans1<<" "<<ans2;
	return 0;
}

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