Hi,

Line  27-30: The main-problem why you received  "TypeError Length Undefined" is because there is no break-command in your if-validation, once the current sum has exceeded the target. Thus, the while-loop keeps on reading data from the array, even though the array has no more further elements.

Line 34: I don't think you need Math.Abs to solve this exercise, toFixed(2) is totally sufficient for the printing the final result.

Possible problem with judge: I have refactored your code, however when validating in judge, it gets 0% because the input can not be of array-type, which does not make sense since the array can have different lengths. So I guess that currently there is a problem with the judge-system, but your solution now works and does not throw any error when running locally on VS-Code.

Refactored code: 

function solve(input) {

let target = Number(input[0]);

// let cocktailName = input[1];

// let cocktailNum = parseInt(input[2]);

let index = 1;

let sum = 0;

// let cocktail = input;

while (index < input.length) {

let cocktailName = input[index];

if (cocktailName === "Party!") {

console.log(`We need ${(target - sum).toFixed(2)} leva more.`);

// console.log("We need " + Math.abs(target - sum).toFixed(2) + " leva more.");

break;

}

// let cocktailName = input[1];

let cocktailNum = Number(input[index + 1]);

let cocktailPrice = (cocktailName.length) * cocktailNum;

if (cocktailPrice % 2 !== 0) {

cocktailPrice *= 0.75;

}

sum += cocktailPrice;

index += 2;

if (sum >= target) {

// console.log("Target acquired");

// console.log("Club income " + sum.toFixed(2) + " leva.");

break;

}

}

if (sum < target) {

// console.log("We need " + Math.abs(target - sum).toFixed(2) + " leva more.");

console.log("Club income " + sum.toFixed(2) + " leva.");

} else {

console.log("Target acquired");

console.log("Club income " + sum.toFixed(2) + " leva.");

}

}

solve(['500', 'Bellini', '6', 'Bamboo', '7', 'Party!']);

solve(['100', 'Sidecar', '7', 'Mojito', '5', 'White Russian', '10']);