find peak element

src/main/java/binarysearch/LeetCode_0162_FindPeakElement.java

@@ -11,31 +11,32 @@ package binarysearch;
 // 二分法
 // 笔记：https://www.cnblogs.com/greyzeng/p/16622554.html
 public class LeetCode_0162_FindPeakElement {
-    public int findPeakElement(int[] nums) {
-        if (nums.length == 1) {
-            return 0;
-        }
-        if (nums.length == 2) {
-            return nums[0] > nums[1] ? 0 : 1;
-        }
-        if (nums[0] > nums[1]) {
-            return 0;
-        }
-        if (nums[nums.length - 1] > nums[nums.length - 2]) {
-            return nums.length - 1;
-        }
-        int l = 1;
-        int r = nums.length - 2;
-        while (l <= r) {
-            int m = l + ((r - l) >> 1);
-            if (nums[m] > nums[m - 1] && nums[m] > nums[m + 1]) {
-                return m;
-            } else if (nums[m] <= nums[m - 1]) {
-                r = m - 1;
-            } else if (nums[m] <= nums[m + 1]) {
-                l = m + 1;
-            }
-        }
-        return -1;
-    }
+	public int findPeakElement(int[] nums) {
+		if (nums.length == 1) {
+			return 0;
+		}
+		if (nums.length == 2) {
+			return nums[0] > nums[1] ? 0 : 1;
+		}
+		int l = 0; 
+		int r = nums.length - 1;
+		while (l <= r) {
+			if (nums[l] > nums[l + 1]) {
+				return l;
+			}
+			if (nums[r] > nums[r - 1]) {
+				return r;
+			}
+			int m = l + ((r - l) >> 1);
+			if (nums[m] > nums[m - 1] && nums[m] > nums[m + 1]) {
+				return m;
+			} else if (nums[m] < nums[m - 1]) {
+				r = m - 1;
+			} else {
+				// nums[m] < nums[m + 1]
+				l = m + 1;
+			}
+		}
+		return -1;
+	}
 }