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