encryption.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++];
}
function getMatrixDimension(s) {
    let len = Math.floor(Math.sqrt(s.length));
    let m = len;
    let n = len + 1;
    if ((m * n) < s.length) {
        m = n = len + 1;
    }
    else if (Math.sqrt(s.length) % 1 === 0) {
        m = n = Math.sqrt(s.length);
    }
    return [m, n];
}
// Complete the encryption function below.
function encryption(s) {
    let [m, n] = getMatrixDimension(s);
    let strindex = 0;
    let grid = [];
    for (let i = 0; i < m; i++) {
        grid[i] = [];
        for (let j = 0; j < n; j++) {
            grid[i][j] = s[strindex] || '';
            strindex++;
        }
    }
    let out = "";
    for (let i = 0; i < n; i++) {
        for (let j = 0; j < m; j++) {
            out += grid[j][i];
        } out += " ";
    }
    return out;
}

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

    const s = readLine();

    let result = encryption(s);

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

    ws.end();
}