#include<bits/stdc++.h>
#define rep(i,a,b) for(int i=a;i<b;i++)
#define rrep(i,a,b) for(int i=a;i>=b;i--)
#define fore(i,a) for(auto &i:a)
#pragma GCC optimize ("-O3")
using namespace std; void _main(); int main() { cin.tie(0); ios::sync_with_stdio(false); _main(); }
//---------------------------------------------------------------------------------------------------
/*---------------------------------------------------------------------------------------------------
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int N; string S;
//--------------------------------------------------------------------------------------------------
void _main() {
    cin >> N >> S;

    int ans = N;
    rep(i, 0, N - 1) {
        if (S[i] == 'x' && S[i + 1] == 'x') {
            ans = i + 1;
            break;
        }
    }
    cout << ans << endl;
}