#include <iostream>

using namespace std;

int main()
{
    int n,k,A[1001],p=0,i1=0,i2=0;
    cin>>n>>k;
    for(int i=1;i<=n;i++)
        cin>>A[i];
    int c=n/k;
    for(int i=1;i<=n-n/k;i=i+n/k)
    {
        for(int j=i+n/k;j<=n;j=j+n/k)
            if(A[i]==A[j])
    {
        int ok=1;
        for(int z=1,x=i+1,y=j+1;z<=n/k-1;x++,y++,z++)
            if(A[x]!=A[y]) ok=0;
        if(ok==1)
        {
            p=1;
            int cnt=1;
            while(i1<=n)
            {
                i1++;
                if(i1>c) {cnt++; c=c+n/k;}
                if(i1==i) i1=n+1;
            }
            i1=cnt;
            cnt=1;
            c=n/k;
            while(i2<=n)
            {
                i2++;
                if(i2>c) {cnt++; c=c+n/k;}
                if(i2==j) i2=n+1;
            }
            i2=cnt;
            i=n;
            j=n+1;
        }
    }
    }
    if(p==0) cout<<"NU";
    else cout<<i1<<" "<<i2;
    return 0;
}