Project Euler - Problem 205: Dice Game

Hello to anyone who is reading this. I have an issue with problem 205 on Project Euler. It seems I have achieved the correct solution, but the code evaluates is as incorrect.

Here’s my solution, sorry for the messy code.

function diceGame() {
  let pColin = probabilityArray(6,6);
  let pPeter = probabilityArray(9,4);
  let peterWins = 0;
  let minPeter = 4;
  let maxPeter = 36

  //For every possible result of Peter's dice throws, calculates the probability that Colin gets a lower result, and adds it to the total.
  for(let i = minPeter; i <= maxPeter; i++){
    peterWins += pPeter[i-1]*accumulatedProbability(i,pColin);
  peterWins = (peterWins.toFixed(7));
  return peterWins;

function accumulatedProbability(num,pArr){
  let res = 0;
  for(let i = 1; i < num; i++){
    res += pArr[i-1];
return res;

//Calculates the probability, given amount of dices and faces of dices, of getting a particular result. Uses some kind of DFS
function probabilityArray(dices, faces){
  let res = Array(dices*faces).fill(0); 
  let singularProbability = 1/(faces**dices) //The probability of getting a given set of throws.
  let currentThrow = 1;
  let currentSum = 1; //Updates the value of the sum of a given set of throws
  let throwValues = Array(dices).fill(1); //shows the current set of throws
  let graphCompleted = false;
  while (!graphCompleted){
      if(currentThrow == 1 && throwValues[0] > faces){
        graphCompleted = true;
      else if(currentThrow == dices){//Evaluating all possible values of the last throw
        while(throwValues[currentThrow-1] <= faces){
          res[currentSum-1]+= singularProbability;
          currentSum ++;
        //after evaluating all possible values, adds one to the second to last throw and continues
        throwValues[currentThrow-1] = 1;
        currentSum = currentSum - faces;
        throwValues[currentThrow-1] ++;    
      //if any non-final throw is less than the amount of faces in the dice, increments its value by one and evaluates the next throw
      else if(throwValues[currentThrow-1] <= faces){
        currentSum ++;

      //When any non-last throw exceeds the number of faces, resets it to one, and increases the previous throw by one.
      else if(throwValues[currentThrow-1] > faces){
        currentSum -= faces;
        throwValues[currentThrow-1] = 1;
return (res)


If you log the result of the function, its output matches the correct result. I tried converting the result into a string, to see if it’s a type problem, but it doesn’t seem so.

Thank you for your help

Challenge: Problem 205: Dice Game

Link to the challenge:

It’s the other way around. Result is expected to be number, but toFixed method returns string.

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Thank you very much, I didn’t know that about toFixed, stupid mistake by my part. Thank you

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