题解 | #字符个数统计#

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())) {
        let tokens = line.trim().split("");
        if (tokens.length == 0) {
            console.log("请输入字符串");
        } else if (tokens.length > 500) {
            console.log("输入的字符串超出范围");
        }

        let charArr = [];
        for (let i = 0; i < tokens.length; i++) {
            if (tokens[i] == 10) {
                break;
            }
            if (tokens[i] < 0 || tokens[i] > 127) {
                continue;
            }
            if (!charArr.includes(tokens[i])) {
                charArr.push(tokens[i]);
            }
        }
        console.log(charArr.length);
    }
})();