检验采用的是for循环对比遍所有数字，问题出在哪了？

#include<iostream>
using namespace std;
int main()
{
	int arr[1001];
	int brr[1001];
	int n;
	int p = 0;
	cin >> n;
	for (int i = 0; i < n; i++)
	{
		cin >> arr[i];
	}
	for (int j = 0; j < n - 1; j++)
	{
		if (arr[j] > arr[j + 1])
			brr[j] = arr[j] - arr[j + 1];
		else if (arr[j + 1] > arr[j])
			brr[j] = arr[j + 1] - arr[j];
	}
	for (int k = 0; k < n - 1; k++)
	{
		for (int m = 0; m < n; m++)
		{
			if (brr[k] == arr[m])
				p++;
		}
	}
	if (p == n - 1)
		cout << "Jolly";
	else
		cout << "Not jolly";
}