C++ 暴力匹配

class ViolenceMatch
{
public:
	int violencematch(string str1, string str2)
	{
		vector<char>s1;
		vector<char>s2;
		for (int i = 0; i < str1.size(); i++)
		{
			s1.push_back(str1[i]);
		}
		for (vector<char>::iterator it = s1.begin(); it!=s1.end(); it++)
		{
			cout << *it << "  ";
		}
		cout << endl;
		for (int i = 0; i < str2.size(); i++)
		{
			s2.push_back(str2[i]);
		}
		for (vector<char>::iterator it = s2.begin(); it != s2.end(); it++)
		{
			cout << *it << "  ";
		}
		cout << endl;
		int s1_len = s1.size();
		int s2_len = s2.size();

		int j = 0;
		int k = 0;
		while (j < s1_len && k < s2_len)
		{
			if (s1[j] == s2[k])
			{
				j++;
				k++;
			}
			else
			{
				j = j - (k - 1);
				k = 0;
			}
		}
		if (k == s2_len)
		{
			return j - k;
		}
		else
		{
			return -1;
		}
	}
};