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 () {
    // Write your code here
    while(line = await readline()){
        // 2个瓶子 借一个空瓶，就可以喝一瓶水，再把瓶子归还
        // 相当于2个瓶子可以喝一瓶水
        if (Number(line) !== 0) {
            console.log(Math.floor(Number(line) / 2))
        }
    }
}()