按题意直接模拟即可。

AC code:

#include <bits/stdc++.h>
using namespace std;

int main() {
    string s;
    cin >> s;
    int ans = 0;
    int n = s.size();
    for (int i = 0; i <= n - 2; i++) {
        if (s[i] == 'g' && s[i+1] == 'j') {
            ans++;
        }
    }
    if (ans == 0) {
        cout << "0" << endl;
    } else {
        string result = "1" + to_string(ans - 1);
        string f;
        for (char c : result) {
            if (c != '0') {
                f += c;
            }
        }
        if (f.empty()) {
            cout << "0" << endl;
        } else {
            cout << f << endl;
        }
    }
    
    return 0;
}