moving-zeros-to-the-end.js

// moveZeros([false,1,0,1,2,0,1,3,"a"]) // returns[false,1,1,2,1,3,"a",0,0]

var moveZeros = function (arr) {
  // a place to store the movedZeros array
  const movedZeros = [];
  // a place to store the zero count
  let zeroCount = 0;

  // iterate over the array
  for (let i = 0; i < arr.length; i++) {
    const value = arr[i];
    // if the current value is not a zero
    if (value !== 0) {
      // push into movedZeros array
      movedZeros.push(value);
    } else {
      // increment zero count
      zeroCount++;
    }
  }

  // iterate up to zero count
  for (let i = 0; i < zeroCount; i++) {
    // push zero into the array
    movedZeros.push(0);
  }

  // return the movedZeros array
  return movedZeros;
}

var moveZeros = function (arr) {
  let zeroCount = 0;
  const movedZeros = arr.reduce((movedZeros, value, index) => {
    if (value !== 0) {
      movedZeros[index - zeroCount] = value;
    } else {
      zeroCount++;
    }
    return movedZeros;
  }, new Array(arr.length).fill(0));

  return movedZeros;
}

// NOT WORKING RIGHT NOW...
var moveZeros = function (arr) {
  let zeroCount = 0;
  for (let i = 0; i < arr.length - zeroCount; i++) {
    const value = arr[i];
    if (value === 0) {
      for (let j = i; j < arr.length - 1 - zeroCount; j++) {
        arr[j] = arr[j + 1];
        arr[arr.length - 1 - zeroCount] = 0;
      }
      zeroCount++;
      i--;
    }
  }

  return arr;
}

console.log(JSON.stringify(moveZeros([1, 2, 1, 0, 1, 0, 3, 0, 1, 0]))),
console.log(JSON.stringify([1, 2, 1, 1, 3, 1, 0, 0, 0, 0]))