search in rotated sorted array

Author: se6816

search-in-rotated-sorted-array/se6816.java

@@ -0,0 +1,46 @@
+class Solution {
+    public int search(int[] nums, int target) {
+        int firstIdx = binarySearch(nums);
+        int result = 0;
+        if (firstIdx == 0) {
+            return binarySearch(target, nums, 0, nums.length - 1);
+        } else if (target >= nums[0]) {
+            return binarySearch(target, nums, 0, firstIdx);
+        } else {
+            return binarySearch(target, nums, firstIdx, nums.length - 1);
+        }
+    }
+
+    public int binarySearch(int[] nums) {
+            int start = 0;
+            int end = nums.length -1;
+            while(start < end) {
+                int mid = (start + end) / 2;
+                if(nums[mid] < nums[end]) {
+                    end = mid;
+                } else {
+                    start = mid + 1;
+                }
+            }
+            return start;
+    }
+
+    public int binarySearch(int target, int[] nums, int start, int end) {
+            int result = -1;
+            while(start <= end) {
+                int mid = (start + end) / 2;
+                if(nums[mid] > target) {
+                    end = mid - 1;
+                } else if(nums[mid] < target){
+                    start = mid + 1;
+                } else {
+                    result = mid;
+                    break;
+                }
+            }
+
+            return result;
+    }
+        
+    
+}