class Solution {
    public int peakValleyDifference(int[] nums) {
        int n=nums.length;
 
        int sum_peak =0;
        int sum_valley =0;
 
        for(int i=1;i<n-1;i++){
            if(nums[i]>nums[i-1] && nums[i]>nums[i+1]){
                sum_peak+=nums[i];
            }
            else if(nums[i]<nums[i-1] && nums[i] <nums[i+1]){
                sum_valley+=nums[i];
            }
        }
 
        return (sum_peak-sum_valley);
    }
}

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