每日一题洛谷P8627 [蓝桥杯 2015 省 A] 饮料换购c++

#include<iostream>
using namespace std;
int main() {
	int n;
	cin >> n;
	int t = (int)(n * 3 - 1) / 2;
	cout << t << endl;
	return 0;
}