题解 | 成绩

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

void (async function () {
    const lines = (await readline()).split(" ");

    const A = parseInt(lines[0]);
    const B = parseInt(lines[1]);
    const C = parseInt(lines[2]);

    if (A >= 0 && B >= 0 && C >= 0 && A <= 100 && B <= 100 && C <= 100) {
        const S = A * 0.2 + B * 0.3 + C * 0.5;
        console.log(S);
    } else {
        console.log("输入数据非法");
    }

    rl.close();
})();