#include<iostream> #include<cstdio> using namespace std; const int NR=10010; int a[NR]; int main() { int n,i,m; cin>>n; for(i=1;i<=n;i++) cin>>a[i]; cin>>m; for(i=1;i<=n;i++) if(a[i]==m) { cout<<i<<endl; return 0; } cout<<"-1\n"; return 0; }