answer3.js

// Bug Version
function createArrayOfFunctions(y) {
    var arr = [];
    for(var i = 0; i<y; i++) {
      arr[i] = function(x) { return x + i; } // <=== the i is bug ! the i will always be y+1;
    }
    return arr;
 }

 // Current Version
function createArrayOfFunctions(y) {
    var arr = [];
    for(var i = 0; i<y; i++) {
        arr[i] = ((i) => {
            return function(x){return x + i;}
        })(i);
    }
    return arr;
}