#include<iostream>
#include<fstream>
#include<algorithm>

using namespace std;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(NULL);

    ifstream  input("phonebook.in");
    ofstream  output("phonebook.out");

    int n;
    string a[50005];

    string a_copy[50005];

    input >> n;
    for(int i = 0;i<n;i++)
    {
        input >> a[i];

        a_copy[i] = a[i];
    }

    sort(a_copy,a_copy+n);
    for(int i = 0;i<n;i++)
    if(a[i]!=a_copy[i]) {output << i+1 << '\n';return 0;}
}