34. Find First and Last Position of Element in Sorted Array (java)

Author: bluesword12350

solution/0034.Find First and Last Position of Element in Sorted Array/Solution.java

@@ -0,0 +1,30 @@
+class Solution {
+    public int[] searchRange(int[] nums, int target) {
+        int start = 0, end = nums.length - 1;
+        while (start <= end) {
+            int mid = start + (end - start) / 2;
+            if (nums[mid] < target) start = mid + 1;
+            else if (nums[mid] > target) end = mid - 1;
+            if (nums[mid] == target) {
+                return new int[]{findFirst(nums, start, mid, target),findEnd(nums, mid, end, target)};
+            }
+        }
+        return new int[]{-1,-1};
+    }
+    private int findFirst(int[] nums, int start, int end, int target) {
+        while (start < end) {
+            int temp = start + (end - start) / 2;
+            if (nums[temp] < target) start = temp + 1;
+            else if (nums[temp] == target) end = temp;
+        }
+        return start;
+    }
+    private int findEnd(int[] nums, int start, int end, int target) {
+        while (start < end) {
+            int temp = start + (end - start + 1) / 2;
+            if (nums[temp] > target) end = temp - 1;
+            else if (nums[temp] == target) start = temp;
+        }
+        return start;
+    }
+}