学步园

题目来自剑指Offer

题目1：

思路：建哈希，检测字符串

代码：

void FindChar(const char* pStr)
{
	assert(pStr);
	int Hash[256];
	int nLen = strlen(pStr);
	memset(Hash,0,sizeof(int) * 256);

	for (int nCur = 0;nCur < nLen;nCur++)
	{
		Hash[pStr[nCur]]++;
	}

	for (int nCur = 0;nCur < nLen;nCur++)//不能直接遍历哈希
	{
		if (Hash[pStr[nCur]] == 1)
		{
			cout<<pStr[nCur]<<endl;
		}
	}
}

代码(2)

void FindChar(char* pStr)
{
	assert(pStr != NULL);
	int nLen = strlen(pStr);
	int nArr[26] = {0};
	int i = 0;
	for (i = 0;i < nLen;i++)
	{
		nArr[ pStr[i] - 'a']++;
	}
	for (int i = 0;i < 26;i++)
	{
		if (nArr[i] == 1)
		{
			cout<< static_cast<char>(i + 'a')<<endl;
			return;
		}
	}
}

题目2：

代码：

bool IsAnagram(const char* pStrOne,const char* pStrTwo)
{
	assert(pStrOne && pStrTwo);
	int Hash[256];
	int nLenStrOne = strlen(pStrOne);
	int nLenStrTwo = strlen(pStrTwo);

	if (nLenStrOne != nLenStrTwo)
	{
		return false;
	}

	memset(Hash,0,sizeof(int) * 256);

	//遍历第一个串建立哈希
	for (int nCur = 0;nCur < nLenStrOne;nCur++)
	{
		Hash[pStrOne[nCur]]++;
	}
	//遍历第二个串处理哈希
	for (int nCur = 0;nCur < nLenStrTwo;nCur++)
	{
		if (Hash[pStrTwo[nCur]] < 1)
		{
			return false;
		}
		Hash[pStrTwo[nCur]]--;
	}
	//遍历哈希，检测是否相等
	for (int nCur = 0;nCur < nLenStrTwo;nCur++)
	{
		if (Hash[pStrTwo[nCur]] != 0)
		{
			return false;
		}
	}
	return true;
}