Solved 3 problems

varunu28 · varunu28 · commit c4f1640fd495 · 2017-12-25T19:49:37.000-08:00
diff --git a/Easy/Lowest Common Ancestor of a Binary Search Tree.java b/Easy/Lowest Common Ancestor of a Binary Search Tree.java
@@ -0,0 +1,23 @@
+/**
+ * Definition for a binary tree node.
+ * public class TreeNode {
+ *     int val;
+ *     TreeNode left;
+ *     TreeNode right;
+ *     TreeNode(int x) { val = x; }
+ * }
+ */
+class Solution {
+    public TreeNode lowestCommonAncestor(TreeNode root, TreeNode p, TreeNode q) {
+        
+        if (root.val < p.val && root.val < q.val) {
+            return lowestCommonAncestor(root.right, p, q); 
+        }
+        else if (root.val > p.val && root.val > q.val) {
+            return lowestCommonAncestor(root.left, p, q); 
+        }
+        else {
+            return root;
+        }
+    }
+}
diff --git a/Medium/Find Minimum in Rotated Sorted Array.java b/Medium/Find Minimum in Rotated Sorted Array.java
@@ -0,0 +1,17 @@
+class Solution {
+    public int findMin(int[] nums) {
+        int low = 0 ;
+        int high = nums.length-1;
+        while(low<high) {
+            int mid = (low+high)/2;
+            if (nums[mid] > nums[high]) {
+                low = mid + 1;
+            }
+            else if (nums[mid] < nums[high]) {
+                high = mid;
+            }
+        }
+        
+        return nums[low];
+    }
+}
diff --git a/Medium/Sort Colors.java b/Medium/Sort Colors.java
@@ -0,0 +1,28 @@
+class Solution {
+    public void sortColors(int[] nums) {
+        int numZero = 0;
+        int numOne = 0;
+        int numTwo = 0;
+        
+        for(int i=0;i<nums.length;i++) {
+            if(nums[i] == 0) numZero++;
+            if(nums[i] == 1) numOne++;
+            if(nums[i] == 2) numTwo++;
+        }
+        
+        for(int i=0;i<nums.length;i++) {
+            if (numZero != 0) {
+                nums[i] = 0;
+                numZero--;
+            }
+            else if(numZero == 0 && numOne != 0) {
+                nums[i] = 1;
+                numOne--;
+            }
+            else {
+                nums[i] = 2;
+                numTwo--;
+            }
+        }
+    }
+}
