题解 | #寻找峰值#

nums[-1] = nums[n] = -∞
1 <= 数组长度 <= 1000
0 <= 数组元素的值 <= 1000

重新创建数组arr，第一个与最后一个元素设为-1，其它元素依次为参数数组a元素，再遍历arr数组，arr.index = [1, a.length]

import java.util.*;


public class Solution {
    /**
     * 寻找最后的山峰
     * @param a int整型一维数组 
     * @return int整型
     */
    public int solve (int[] a) {
        // write code here
        int[] arr = new int[a.length + 2];
        arr[0] = -1;
        arr[a.length + 1] = -1;

        for (int i = 0; i < a.length; i ++) {
            arr[i + 1] = a[i];
        }

        // 峰值索引
        int index = -1;

        for (int i = 1; i < a.length + 1; i++) {

            boolean boo = (arr[i] > arr[i - 1] && arr[i] > arr[i + 1]) 
                    || (arr[i] == arr[i - 1] && arr[i] == arr[i + 1]); 

                if (boo) {
                    index = i - 1;
                }        
        }
        return index;
    }
}