Question 7 - Missing Number

Given an array containingndistinct numbers taken from0, 1, 2, ..., n, find the one that is missing from the array.

For example,
Givennums=[0, 1, 3]return2.

Note:
Your algorithm should run in linear runtime complexity. Could you implement it using only constant extra space complexity?

Solution

/**
 * @param {number[]} nums
 * @return {number}
 */
var missingNumber = function(nums) {
  var i;
  nums.sort(function(a,b){
    return a - b;
  })
  for(i = 0; i < nums.length; i++){
   if(nums.indexOf(i) !== i){
     return i;
   }
  }

  return i;
};

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