Find largest mountain in the array

Tushar Roy · Tushar Roy · commit 94be5deb0c0d · 2018-07-29T17:37:26.000-07:00
diff --git a/src/com/interview/array/LargestMountain.java b/src/com/interview/array/LargestMountain.java
@@ -0,0 +1,45 @@
+package com.interview.array;
+
+/**
+ * https://leetcode.com/problems/longest-mountain-in-array/description/
+ */
+public class LargestMountain {
+
+    public int longestMountain(int[] nums) {
+        int start = 0;
+        int max = 0;
+        State state = State.STARTED;
+        for (int i = 1; i < nums.length; i++) {
+            if (nums[i] == nums[i - 1]) {
+                start = i;
+                state = State.STARTED;
+            }
+            else if (nums[i] > nums[i - 1]) {
+                if (state == State.DECREASING || state == State.STARTED) {
+                    start = i - 1;
+                    state = State.INCREASING;
+                }
+            } else {
+                if (state == State.INCREASING || state == State.DECREASING) {
+                    state = State.DECREASING;
+                    max = Math.max(max, i - start + 1);
+                } else {
+                    start = i;
+                }
+            }
+        }
+        return max;
+    }
+
+    enum State {
+        STARTED,
+        INCREASING,
+        DECREASING;
+    }
+
+    public static void main(String[] args) {
+        LargestMountain lm = new LargestMountain();
+        int[] nums = {2, 1, 4, 7, 3, 2, 5};
+        System.out.println(lm.longestMountain(nums));
+    }
+}
