add a solution for 34

fishercoder1534 · fishercoder1534 · commit 19e7a1b64457 · 2021-04-29T07:31:21.000-07:00
diff --git a/src/main/java/com/fishercoder/solutions/_34.java b/src/main/java/com/fishercoder/solutions/_34.java
@@ -2,49 +2,87 @@
 
 public class _34 {
 
-    public int[] searchRange(int[] nums, int target) {
-        int[] range = new int[2];
-        range[0] = -1;
-        range[1] = -1;
-        if (nums == null || nums.length == 0) {
-            return range;
-        }
-        int start = 0;
-        int end = nums.length - 1;
-        while (start + 1 < end) {
-            int mid = start + (end - start) / 2;
-            if (nums[mid] == target) {
-                int left = mid;
-                while (left - 1 >= 0 && nums[left] == nums[left - 1]) {
-                    left--;
+    public static class Solution1 {
+        public int[] searchRange(int[] nums, int target) {
+            int[] range = new int[2];
+            range[0] = -1;
+            range[1] = -1;
+            if (nums == null || nums.length == 0) {
+                return range;
+            }
+            int start = 0;
+            int end = nums.length - 1;
+            while (start + 1 < end) {
+                int mid = start + (end - start) / 2;
+                if (nums[mid] == target) {
+                    int left = mid;
+                    while (left - 1 >= 0 && nums[left] == nums[left - 1]) {
+                        left--;
+                    }
+                    range[0] = left;
+                    int right = mid;
+                    while (right + 1 < nums.length && nums[right] == nums[right + 1]) {
+                        right++;
+                    }
+                    range[1] = right;
+                    break;
+                } else if (nums[mid] < target) {
+                    start = mid;
+                } else {
+                    end = mid;
+                }
+            }
+
+            if (nums[start] == target) {
+                range[0] = start;
+                while (start + 1 < nums.length && nums[start] == nums[start + 1]) {
+                    start++;
                 }
-                range[0] = left;
-                int right = mid;
-                while (right + 1 < nums.length && nums[right] == nums[right + 1]) {
-                    right++;
+                range[1] = start;
+            } else if (nums[end] == target) {
+                range[1] = end;
+                while (end - 1 >= 0 && nums[end] == nums[end - 1]) {
+                    end--;
                 }
-                range[1] = right;
-                break;
-            } else if (nums[mid] < target) {
-                start = mid;
-            } else {
-                end = mid;
+                range[0] = end;
             }
+            return range;
         }
+    }
 
-        if (nums[start] == target) {
-            range[0] = start;
-            while (start + 1 < nums.length && nums[start] == nums[start + 1]) {
-                start++;
+    public static class Solution2 {
+        public int[] searchRange(int[] nums, int target) {
+            int[] result = new int[]{-1, -1};
+            if (nums == null || nums.length == 0) {
+                return result;
+            }
+            if (nums[0] > target) {
+                return result;
             }
-            range[1] = start;
-        } else if (nums[end] == target) {
-            range[1] = end;
-            while (end - 1 >= 0 && nums[end] == nums[end - 1]) {
-                end--;
+            if (nums[nums.length - 1] < target) {
+                return result;
+            }
+            int left = 0;
+            int right = nums.length - 1;
+            while (left <= right) {
+                int mid = left + (right - left) / 2;
+                if (nums[mid] == target) {
+                    while (mid - 1 >= 0 && nums[mid] == nums[mid - 1]) {
+                        mid--;
+                    }
+                    result[0] = mid;
+                    while (mid + 1 < nums.length && nums[mid] == nums[mid + 1]) {
+                        mid++;
+                    }
+                    result[1] = mid;
+                    return result;
+                } else if (nums[mid] > target) {
+                    right = mid - 1;
+                } else {
+                    left = mid + 1;
+                }
             }
-            range[0] = end;
+            return result;
         }
-        return range;
     }
 }
diff --git a/src/test/java/com/fishercoder/_34Test.java b/src/test/java/com/fishercoder/_34Test.java
@@ -7,23 +7,27 @@
 import static org.junit.Assert.assertArrayEquals;
 
 public class _34Test {
-    private static _34 test;
+    private static _34.Solution1 solution1;
+    private static _34.Solution2 solution2;
     private static int[] nums;
 
     @BeforeClass
     public static void setup() {
-        test = new _34();
+        solution1 = new _34.Solution1();
+        solution2 = new _34.Solution2();
     }
 
     @Test
     public void test1() {
         nums = new int[]{1, 2, 3};
-        assertArrayEquals(new int[]{1, 1}, test.searchRange(nums, 2));
+        assertArrayEquals(new int[]{1, 1}, solution1.searchRange(nums, 2));
+        assertArrayEquals(new int[]{1, 1}, solution2.searchRange(nums, 2));
     }
 
     @Test
     public void test2() {
         nums = new int[]{};
-        assertArrayEquals(new int[]{-1, -1}, test.searchRange(nums, 0));
+        assertArrayEquals(new int[]{-1, -1}, solution1.searchRange(nums, 0));
+        assertArrayEquals(new int[]{-1, -1}, solution2.searchRange(nums, 0));
     }
 }
