题解 | #汽水瓶#

package main

import (
    "fmt"
)

func drinkWater(emptyCup int) int {
    var drinkCup int

    for emptyCup >= 3 {
        drinkCup += emptyCup / 3
        emptyCup = emptyCup % 3 + emptyCup / 3
        // fmt.Printf("drink: %d, emptyCup: %d\n", drinkCup, emptyCup)
    }

    if emptyCup == 2 {
        drinkCup++
    }

    return drinkCup
}

func main() {
    for true {
        var emptyCup int
        fmt.Scan(&emptyCup)
        if emptyCup == 0 {
            break
        }

        fmt.Println(drinkWater(emptyCup))
    }
}

// 本题每行输入为一个整数，所以采用： fmt.Scan(&n)