字符串排列组合

bool BiggerFirst(string s1,string s2)
{
	int size=s1.size();
	for (int i = 0; i < size; i++)
	{
		if (s1[i]>s2[i])
		{
			return true;		
		}
		else if (s1[i]<s2[i])
		{
			return false;
		}
	}
	return true;

}
vector<string> makeNew(string s,char c)
{
	string temp;
	temp.reserve(s.size()+1);
	temp.resize(s.size()+1);
	vector<string> s1(s.size()+1,temp);
	for (int i = 0; i <=s.size(); i++)
	{
		s1[i][i]=c;
		if (i==0)
		{
			for (int j = 1; j <=s.size(); j++)
			{
				s1[i][j]=s[j-1];
			}
		}
		else if (i==s.size())
		{
			for (int j = 0; j < s.size(); j++)
			{
				s1[i][j]=s[j];
			}
		}
		else
		{
			for (int j = 0; j <i; j++)
			{
				s1[i][j]=s[j];
			}
			for (int j= i+1; j <=s.size(); j++)
			{
				s1[i][j]=s[j-1];
			}
		}

	}
	return s1;
}
 vector<string> getPermutation(string A)
{
	vector<vector<string>> s;
	vector<string> a(1,string(1,A[0]));
	s.reserve(20);
	s.resize(20);
	s[0]=a;
	for (int i = 1; i < A.size(); i++)
	{
		for (auto&tag1:s[i-1])
		{
			vector<string> temp;
			temp=makeNew(tag1,A[i]);
			for (auto& tag2:temp)
			{
				s[i].push_back(tag2);
			}
		}
	}
	vector<string> result=s[A.size()-1];
	for (int i = 1; i < result.size()-1; i++)
	{
		int j=i-1;
		while (BiggerFirst(result[i],result[j]))
		{
			j--;
		
		}
		if (i>j+1)
		{
			string temp=result[i];
			for (int Count = i; Count >j+1; Count--)
			{
				result[Count]=result[Count-1];
			}
			result[j+1]=temp;

		}	
	}
	return result;
}