diff --git a/leetcode/array/MakeTwoArraysEqualByReversingSubarrays.java b/leetcode/array/MakeTwoArraysEqualByReversingSubarrays.java new file mode 100644 index 00000000..609827d9 --- /dev/null +++ b/leetcode/array/MakeTwoArraysEqualByReversingSubarrays.java @@ -0,0 +1,41 @@ +// 1460. Make Two Arrays Equal by Reversing Sub-arrays +//You are given two integer arrays of equal length target and arr. In one step, you can select any non-empty sub-array of arr and reverse it. You are allowed to make any number of steps. +// +//Return true if you can make arr equal to target or false otherwise. +// +//Example 1: +// +//Input: target = [1,2,3,4], arr = [2,4,1,3] +//Output: true +//Explanation: You can follow the next steps to convert arr to target: +//1- Reverse sub-array [2,4,1], arr becomes [1,4,2,3] +//2- Reverse sub-array [4,2], arr becomes [1,2,4,3] +//3- Reverse sub-array [4,3], arr becomes [1,2,3,4] +//There are multiple ways to convert arr to target, this is not the only way to do so. +//Example 2: +// +//Input: target = [7], arr = [7] +//Output: true +//Explanation: arr is equal to target without any reverses. +//Example 3: +// +//Input: target = [3,7,9], arr = [3,7,11] +//Output: false +//Explanation: arr does not have value 9 and it can never be converted to target. + +public class MakeTwoArraysEqualByReversingSubarrays { + public boolean canBeEqual(int[] target, int[] arr) { + if(target.length != arr.length) return false; + Map map = new HashMap<>(); + for(int i = 0; i < target.length; i++){ + map.put(target[i], map.getOrDefault(target[i], 0) + 1); + } + for(int i = 0; i < arr.length; i++){ + if(map.containsKey(arr[i])){ + map.put(arr[i], map.getOrDefault(arr[i], 0) - 1); + if(map.get(arr[i]) == 0) map.remove(arr[i]); + } + } + return map.size() == 0; + } +} \ No newline at end of file