看了诸位大佬的改了好几个小时也还是死循环，人已经坏掉了，求求各位大佬救一下

#include<iostream>
#include<vector>
#include<string>
#include<set>

using namespace std;

set<string> s[20];

int solution(int m, int size, string& target)
{
	vector<bool> dp(size + 1, false);
	dp[0] = true;
	int ans = 0;
	for (int i = 1; i < dp.size(); i++)
	{
		for (int j = m > i ? i : m; j > 0; j--)
		{
			string temp = target.substr(i - j, j);
			if (s[j].count(temp) && dp[i - j])
			{
				dp[i] = true;
				ans = i;
				break;
			}
		}
	}
	return ans;

}

int main()
{
	string target;
	string temp;
	int m;
	while (cin >> temp && temp != ".")
	{
		s[temp.size()].insert(temp);
		m = max(m, int(temp.size()));
	}
	cin.tie(nullptr);
	char ch;
	while ((ch = getchar()) != EOF)
		if(isalpha(ch))
			target = target + temp;
	int size = target.size();
	int ans = solution(m, size, target);
	cout << ans;
	return 0;
}