面试题14：调整数组顺序使奇数位于偶数前面

void ReorderOddEven_1(int *pData, unsigned int length)
{
if (pData == NULL || length <= 0)
return;
int start = 0;
int end = length - 1;
while (start < end)
{
while (start < end && pData[start] % 2 != 0)
start++;
while (start < end && pData[end] % 2 == 0)
end--;
if (start < end)
{
int temp = pData[start];
pData[start] = pData[end];
pData[end] = temp;
}
}
}

void ReorderOddEven_1(int *pData, unsigned int length)
{
if(pData == NULL || length == 0)
return;

int *pBegin = pData;
int *pEnd = pData + length - 1;

while(pBegin < pEnd)
{
// 向后移动pBegin，直到它指向偶数
while(pBegin < pEnd && (*pBegin & 0x1) != 0)
pBegin ++;

// 向前移动pEnd，直到它指向奇数
while(pBegin < pEnd && (*pEnd & 0x1) == 0)
pEnd --;

if(pBegin < pEnd)
{
int temp = *pBegin;
*pBegin = *pEnd;
*pEnd = temp;
}
}
}