C语言双指针算法朋友过情人节我过算法

void hit(int *arr,int arrsize)
{
int* left = arr;
int* right = arr + arrsize -1;
while(left<=right)
{
条件语句;
left++;
条件语句;
right--;
}
}

void speed(int *arr)
{
   int* fast = arr;
   int* slow = arr;
   while(slow<fast)
   {
   条件;
   slow++(非条件下fast++);
   }
}

void speed(int *arr)
{
int* slow =arr;
int* fast = arr;
while(条件1)
{
slow++;
}
while(条件2)
{
fast++;
}
}

int* reOrderArray(int* array, int arrayLen, int* returnSize ) {
  *returnSize = arrayLen;
   int* left = array;
	int* right = array + arrayLen - 1;
	while (left < right)//(1)
	{
		while (left < right && *left % 2 == 1)//(2)
			left++;
		while (left < right && *right % 2 == 0)//(3)
			right--;
		if (left < right)//(4)
		{
			int tmp = *left;
			*left = *right;
			*right = tmp;
		}
		left++;
		right--;
	}
	return array;
}

int removeElement(int* nums, int numsSize, int val) {
	int* p1 = nums;
	int* p2 = nums;
	int sz = numsSize;
	for (; p1 < nums + numsSize; p1++)
	{
		if (*p1 != val)
		{
			*p2 = *p1;
			*p2++;
		}
		else
			sz--;
	}
	return sz;
}