happy-ladybugs.js

'use strict';

const fs = require('fs');

process.stdin.resume();
process.stdin.setEncoding('utf-8');

let inputString = '';
let currentLine = 0;

process.stdin.on('data', inputStdin => {
    inputString += inputStdin;
});

process.stdin.on('end', _ => {
    inputString = inputString.replace(/\s*$/, '')
        .split('\n')
        .map(str => str.replace(/\s*$/, ''));

    main();
});

function readLine() {
    return inputString[currentLine++];
}

// Complete the happyLadybugs function below.
function happyLadybugs(b) {
    var obj = {};
    let s1 = b;
    for (var i = 0; i < s1.length; i++) {
        if (typeof obj[s1[i]] === 'undefined') {
            obj[s1[i]] = 1;
        } else {
            obj[s1[i]] = obj[s1[i]] + 1;
        }
    }
    for (var i in obj) {
        if (i !== '_' && obj[i] === 1)
            return "NO";
    }
    if (b.indexOf('_') !== -1)
        return "YES";
    for (var i = 1; i < b.length; i++) {
        if (b[i] === b[i - 1] || b[i] === b[i + 1])
            continue;
        else
            return "NO";
    }
    return "YES";
}

function main() {
    const ws = fs.createWriteStream(process.env.OUTPUT_PATH);

    const g = parseInt(readLine(), 10);

    for (let gItr = 0; gItr < g; gItr++) {
        const n = parseInt(readLine(), 10);

        const b = readLine();

        let result = happyLadybugs(b);

        ws.write(result + "\n");
    }

    ws.end();
}