#include <stdio.h>

int findPosition(int arr[], int n, int target){
    for (int i = 0; i < n; i++){
        if (arr[i] == target) {
            return i + 1;
        }
    }
    return -1;
}
int main(){
    int n;
    scanf("%d", &n);
    
    int arr[n];
    for (int i = 0; i < n; i++){
        scanf("%d", &arr[i]);
    }
    int target;
    scanf("%d", &target);
    printf("%\d",findPosition(arr, n, target));
    return 0;
}