Completed Two-Pointers-1

SortColours.java

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+// Time Complexity : O(n)
+// Space Complexity : O(1)
+// Did this code successfully run on Leetcode : yes
+// Any problem you faced while coding this : no
+
+// Your code here along with comments explaining your approach
+/*
+Assign low, mid and high pointers whose ideal task is to point at 0,1 and 2 respectively.Move the mid
+pointer and swap its values with low and high when found 0,2 to sort them at their positions.This way, we
+eventually will have all 0s' at left, all 1's at middle and all 2's at extreme right end.
+ */
+class Solution {
+    public void sortColors(int[] nums) {
+        int low = 0, mid = 0 , high = nums.length - 1;
+        while(mid <= high) {
+            if(nums[mid] == 2) {
+                swap(nums, mid, high);
+                high--;
+            }
+            else if(nums[mid] == 0) {
+                swap(nums, low, mid);
+                low++;
+                mid++;
+            }
+            else
+                mid++;
+        }
+    }
+
+    private void swap(int[] nums, int a, int b) {
+        int temp = nums[a];
+        nums[a] = nums[b];
+        nums[b] = temp;
+    }
+}