#include<bits/stdc++.h> using namespace std; int a[2001]; int main(){ int n,m,b =0,z =0; cin >> n; for(int i = 1;i<=n;i++){ cin >> a[i]; } cin >> m; for(int i = 1;i<=n;i++){ if(a[i] == m){ if(b == 0){ b = i; } z = i; } } if(b == 0){ cout << "-1"; }else{ cout << b <<" " << z; } return 0; }