#include <iostream>
using namespace std;
int main() {
int n;
cin>>n;
int arr[n];
for(int i=0;i<n;i++)
{
int element;
cin>>element;
arr[i]=element;
}
int x;
cin>>x;
int ans=-1;
int low=0, high=n-1;
while(low<=high){
int mid=(low+high)/2;
if(arr[mid]<=x){
low=mid+1;
}
else if(arr[mid]>x){
if(mid==0)
{
ans=mid;
break;
}
else{
if(arr[mid-1]>x)
high=mid-1;
else
ans=mid;
high = mid - 1;
}
}
}
cout<<ans;
return 0;
}
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