#include <bits/stdc++.h>
using namespace std;
int main(){
    int n,s,k;
    cin>>n>>s>>k;
    vector<int> a(n);
    for(auto& aa:a)cin>>aa;
    int idx=0,diff=1e9;
    for(int i=0;i<n;i++){
        if(abs(a[i]-s)<=k){
            if(diff>abs(a[i]-s)){
                idx=i;
                diff=abs(a[i]-s);
            }
        }
    }
    if(diff==1e9){
        cout<<"Unlucky!"<<endl;
    }else{
        cout<<idx+1<<endl;
    }
    return 0;
}