JSFiddle - React, Tailwind, and code Playground

by Prathameshsb

JavaScript

function test(arr) {
	let left = 0, right = arr.length - 1;
	
  while(left < right) {
  	const mid = Math.floor((left + right)/2);
    
    if(arr[mid] > arr[mid+1]){
    	right = mid;
    }else {
    	left = mid + 1
    }
  }
  
  return left;
}

console.log(test([1,2,3,1]));