added 33-Search In Rotated Sorted Array

java/33-Search-In-Rotated-Sorted-Array.java

@@ -0,0 +1,46 @@
+class Solution {
+    public int search(int[] nums, int target) {
+        int minIndex = minIndex(nums);
+        int leftSearch = binarySearch(nums, 0, minIndex - 1, target);
+        int rightSearch = binarySearch(nums, minIndex, nums.length - 1, target);
+        if(leftSearch != -1){
+            return leftSearch;
+        } else if(rightSearch != -1){
+            return rightSearch;
+        } else {
+            return -1;
+        }
+    }
+
+    public int minIndex(int[] nums){
+        int start = 0;
+        int end = nums.length - 1;
+        while(start <= end){
+            int mid = start + (end - start)/2;
+            int prev = (mid - 1 + nums.length)%nums.length;
+            int next = (mid + 1)%nums.length;
+            if(nums[mid] <= nums[prev] && nums[mid] <= nums[next]){
+                return mid;
+            } else if(nums[mid] <= nums[end]){
+                end = mid - 1;
+            } else if(nums[mid] >= nums[start]){
+                start = mid + 1;
+            }
+        }
+        return -1;
+    }
+
+    public int binarySearch(int[] nums, int start, int end, int target){
+        while(start <= end){
+            int mid = start + (end-start)/2;
+            if(nums[mid] == target){
+                return mid;
+            } else if(nums[mid] < target){
+                start = mid + 1;
+            } else {
+                end = mid - 1;
+            }
+        }
+        return -1;
+    }
+}