求教为什么样例过了，提交0分

#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<math.h>
void rank1(int arr[], int left, int right)//left:开始的下标，right：结束的下标。
{
	int right1 = right;
	int left1 = left;
	int ret = arr[left1];
	if (left < right)
	{
		while (left < right)
		{
			while ((left < right) && (arr[right] >= ret))
			{
				right--;
			}
			arr[left] = arr[right];
			if (left != right)
				left++;
			while ((left < right) && (arr[left] <= ret))
			{
				left++;
			}
			arr[right] = arr[left];
			if (left != right)
				right--;
		}
		arr[left] = ret;
		rank1(arr, left1, left - 1);
		rank1(arr, right + 1, right1);
	}
}
int main()
{
	int n = 0;
	int max = 0;
	int count = 0;
	int arr[1000] = { 0 };
	scanf("%d", &n);
	for (int i = 0; i < n; i++)
	{
		scanf("%d", &arr[i]);
	}
	rank1(arr, 0, n - 1);
	for (int i = 0; i < n - 1; i++)
	{
		if (arr[i] == arr[i + 1])
			continue;
		else if (arr[i] + 1 == arr[i + 1])
		{
			count++;
			if (max < count)
				max = count;
		}
		else
			count = 0;
	}
	printf("%d", max);
	return 0;
}