LeetCode [1213] Intersection of Three Sorted Arrays

 1213. Intersection of Three Sorted Arrays

Easy

Given three integer arrays arr1, arr2 and arr3 sorted in strictly increasing order, return a sorted array of only the integers that appeared in all three arrays.

 

Example 1:

Input: arr1 = [1,2,3,4,5], arr2 = [1,2,5,7,9], arr3 = [1,3,4,5,8]
Output: [1,5]
Explanation: Only 1 and 5 appeared in the three arrays.

 

Constraints:

• 1 <= arr1.length, arr2.length, arr3.length <= 1000
• 1 <= arr1[i], arr2[i], arr3[i] <= 2000

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class Solution { public List<Integer> arraysIntersection(int[] arr1, int[] arr2, int[] arr3) { List<Integer> ret = new ArrayList<Integer>(); int i1 = 0, i2 = 0, i3 = 0; while (i1 < arr1.length && i2 < arr2.length && i3 < arr3.length) { int v1 = arr1[i1], v2 = arr2[i2], v3 = arr3[i3]; if (v1 == v2 && v2 == v3) { ret.add(v1); i1++; i2++; i3++; } else if (v1 <= v2 && v1 <= v3) { i1++; } else if (v2 <= v1 && v2 <= v3) { i2++; } else { i3++; } } return ret; } }