题解 | #汽水瓶#

const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;

void async function () {
    while(line = await readline()){
        let num = parseInt(line);
        if(num === 0) break;
        let res = 0;
        while(num>=3){
            let temp = Math.floor(num/3);
            res += temp;
            num = num - temp*2;
        }
        console.log(res+Math.floor((num+1)/3));//Math.floor((num+1)/3)代表向老板借个瓶子
    }
}()