20PTS

#include <bits/stdc++.h>
using namespace std;
long long a, b, c, d, e = 1, f = -1000000000, g, ntm, hhh, aaa, PP, HH, SS, ls, ls1, ls2;
char s[100005];
int P[100005], H[100005], S[100005];
int main() {
    cin >> a;
    for (int i = 1; i <= a; i++) {
        cin >> s[i];
        if (s[i] == 'P') {
            PP++;
            g++;
        } else if (s[i] == 'H') {
            ntm++;
            HH++;
        } else {
            SS++;
            hhh++;
        }
        P[i] = g;
        H[i] = ntm;
        S[i] = hhh;
        // cout<<P[i]<<H[i]<<S[i]<<endl;
    }
    g = 0;
    ntm = 0;
    hhh = 0;
    for (int i = 1; i <= a - 1; i++) {
        g = max(max(P[i], H[i]), max(H[i], S[i]));
        ls = PP - P[i];
        ls1 = HH - H[i];
        ls2 = SS - S[i];
        hhh = max(max(ls, ls1), max(ls1, ls2));
    }
    cout << hhh + g;
}

验证码7779祭