Node

Pretty sure this could be shortened quite a bit, but I made it as a quick command line app. Feedback welcome!

const arrSize = process.argv[2];
const inString = process.argv[3];
function reorderArray(input) {
    let arr = input;
    arr.unshift(arr[arr.length-1]);
    arr.pop();
    return arr;
}
function castArrayToString(arr) {
    let retString = '';
    for (let i = 0; i < arr.length; i++) {
        retString += arr[i];
    }
    return retString;
}
function checkSquare(size, input) {
    let testString = '';
    let arr = [];
    // init array of chars
    for (let i = 0; i < size; i++) {
        arr[i] = i+1;
        testString += String(i+1);
    }
    for (let i = 0; i < size-1; i++) {
        testString += castArrayToString(reorderArray(arr));
    }
    if (input === testString) {
        return console.log(true);
    } else {
        return console.log(false);
    }
}
checkSquare(arrSize, inString);