SOURCE

function searchInsert(nums: number[], target: number): number {
    let l = 0;
  	let r = nums.length - 1;
  	while(l <= r){
      let mid = l + Math.floor((r-l)/2);
      if(nums[mid] == target){
        return mid
      }else if(nums[mid]<target){
        l = mid + 1;
      }else if(nums[mid]>target){
		r = mid -1
      }
    }
};
console.log(searchInsert([1,3,5,6], 2))