#include <iostream>
#include <algorithm>
int binarySearch(int val, int *a, int first, int last) {
  if (first>last) return -1;
  int mid = first+(last-first)/2;
  if (a[mid]==val) return mid;
  // recursive
  if (val<a[mid]) return binarySearch(val,a,first,mid-1);
  else return binarySearch(val,a,mid+1,last);
}
int main(int argc, char* argv[]) {
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  int n; std::cin>>n;
  int array[n];
  for(int i=0;i<n;i++) {
    std::cin>>array[i];
  }
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  //Which value?
  int v; std::cin>>v;
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  //Sort before sending the function.
  std::sort(array, array+n);
  std::cout << "Position: " << binarySearch(v,array,0,n) << std::endl;;
  return 0;
}