计算子字符串出现的次数

int CountSubStr(const char* src, const char* cmp)
{
	int count = 0;
	if (!src || ! cmp)
	{
		return count;
	}
	
	int src_len = strlen(src); 
	int cmp_len = strlen(cmp);

	char *s = const_cast<char*>(&src[0]);
        char *q = const_cast<char*>(&cmp[0]);

	for (int i = 0; i < src_len; ++i)
	{
		if ( s[i] == *q)
		{
			bool match = true;
			int k = 0;
			for (int j = i, k = 0; j < cmp_len, k < cmp_len; ++j, ++k)
			{
				if (s[j] != q[k])
				{
					match = false;
					break;
				}
			}

			if (match)
			{
				count++;
				i+=cmp_len-1;
			}
		}
	}

	return count;
}