last string length

Question

How can I get length of last string in array;What's wrong in here
I'm begginer so sorry
(C++)

#include <iostream>
#include <string>
using namespace std;
int n,z;

int main(){
cin>>n;
string a[n];

for(int i=1;i<=n;i++){
cin>>a[i];
}
z=a[n].length();
cout<<z;

}

Answer 1

sizeof(a[n]) instead of .length() I think