#include<bits/stdc++.h>
#define pb emplace_back
using namespace std;
using ll = long long;
#ifdef KEV
#define DE(i, e) cerr << #i << ' ' << i << e
void debug(auto L, auto R) { while (L < R) cerr << *L << " \n"[L+1==R], ++L; }
#else
#define DE(...) 0
void debug(...) {}
#endif
const int maxn = 1000010;
int n, pf[maxn], v[maxn], dpl[maxn], dpr[maxn], sl[maxn], sr[maxn];
char w[maxn];
int solve(int *dp) {
    static int cnt;
    ++cnt;
    for (int i = 1;i <= n;++i)
        pf[i] = pf[i-1] + v[i];
    stack<int> st;
    st.push(0);
    int res = 0;
#define DP(i) (cnt==1?dp[i] : dp[n-i+1])
    for (int i = 1;i <= n;++i) {
        while (st.size() &&
                pf[st.top()] > pf[i])
            st.pop();

        DP(i) = st.empty() ? 0 : DP(st.top()) + i - st.top();
        st.push(i);
    }
    return res;
}
signed main(){
    ios_base::sync_with_stdio(0), cin.tie(0);
    cin >> n >> w+1;
    for (int i = 1;i <= n;++i)
        v[i] = w[i] != 'j' ? 1 : -1;
    solve(dpl);
    reverse(v+1, v+1+n);
    solve(dpr);
    for (int i = 1;i <= n;++i)
        sr[i] = max(sr[i-1], dpl[i] + i - 1);
    sl[n+1] = n+1;
    for (int i = n;i >= 1;--i)
        sl[i] = min(sl[i+1], i - dpr[i] + 1);
}