#include<bits/stdc++.h> using namespace std; int a[10000]; int main(){ int n,b; cin>>n; for(int i=1;i<=n;i++){ cin>>a[i]; } cin>>b; int s,c; for(int i=1;i<=n;i++){ if(a[i]==b&&s==0){ s=i; } if(a[i]==b){ c=i; } } if(x==0) cout<<-1; else cout<<x<<" "<<y; return 0; }