/**

* @param {number[]} nums

* @return {number}

*/

var firstMissingPositive = function(nums) {

const arrLen = nums.length;

const newArray = new Array(arrLen);

for (let index = 0; index < arrLen; index++) {

const element = nums[index];

if (element > 0 && element <= arrLen) {

(newArray[element-1] > 0 ? newArray[element-1] += 1 : newArray[element-1] = 1);

}

}

let i = 0;

while (newArray[i] && i<arrLen) {

i++;

};

return i+1;

};