https://www.luogu.com.cn/record/115044135

# include <iostream>
using namespace std;
int main(){
    int n;
    cin >> n;
    if (n < 100) cout << "00" << endl;
    else if (n >= 100 && n < 1000) cout << '0' << n / 100 << endl;
    else if (n >= 1000 && n <= 5000) cout << n / 100 << endl;
    else if (n > 5000 && n <= 30000) cout << n / 1000 + 50 << endl;
    else if (n > 30000 && n <= 70000) cout << (n / 1000 - 30) / 5 + 80 << endl;
    return 0;
}