#include <bits/stdc++.h> using namespace std; int main() { int n = 0; while (scanf("%d", &n) != EOF) { int arr[200]; int x = 0, j = 0, xiabiao = -1; for (int i = 0; i < n; i++) { scanf("%d", &arr[i]); } scanf("%d", &x); for (j = 0; j < n; ++j) { if (arr[j] == x) { xiabiao = j; break; }//查到了记得break } cout << xiabiao << endl; } return 0; }