JSFiddle - React, Tailwind, and code Playground

by ronilan

HTML

// find common elements in arrays

JavaScript

function findCommonElementsPointers (arrA, arrB) {

	var result = [];
  var i = 0;
 	var j = 0;
  var maxA = arrA.length;
  var maxB = arrB.length;
      
  while (i < maxA && j < maxB) {
  	if(arrA[i] === arrB[j]) {
    	result.push(arrA[i]);
     	i++;
    	j++;
    } else if (arrA[i] > arrB[j]) {
      j++;
    } else if (arrA[i] < arrB[j]){
      i++;  
    }
  }
	return result;

}

function findCommonElementsBrute (arrA, arrB) {

	var result = [];
  var maxA = arrA.length;
  var maxB = arrB.length;
  var i,
  		j;
      
  for (i = 0; i < maxA; i++) {
    for (j = 0; j < maxB; j++) {
			if (arrA[i] === arrB[j]) {
      	result.push(arrA[i]);
      }
    }  
  }
	return result;

}

var arrA = [1, 5, 15, 20, 30, 37];
var arrB = [2, 5, 13, 30, 32, 35, 37, 42];

console.log(findCommonElementsBrute (arrA, arrB));
console.log(findCommonElementsPointers (arrA, arrB));

var arrA = [116];
var arrB = [115];

console.log(findCommonElementsBrute (arrA, arrB));
console.log(findCommonElementsPointers (arrA, arrB));