#include<iostream> #include<cstdio> using namespace std; int main(){ int i,n,m,begin,end,f=0; cin>>n; int a[n+1]; for (i=1;i<=n;i++) cin>>a[i]; cin>>m; for (i=1;i<=n;i++){ if(a[i]==m){ f=1; begin=i; break; } } for (i=n;i>=1;i--){ if(a[i]==m){ end=i; break; } } if(f==1) cout<<begin<<" "<<end; else cout<<-1; return 0; }