清华大学机试 需要二刷 *贪心算法，比较虎人

#include<iostream>
#include<vector>
#include<algorithm>
#include<string>
#include<cmath>
#include<set>
using namespace std;

const int maxn = 5010;
int n,m;
int dp[maxn][maxn];

vector<string>v1;
vector<string>v2;

int main() {
    while (cin>>n){
        string s;
        for (int i = 0; i < n; i++) {
            cin >> s;
            v1.push_back(s);
        }
        cin >> m;
        for (int i = 0; i < m; i++) {
            cin >> s;
            v2.push_back(s);
        }
        int cnt = 0;
        int index = 0;
        bool flag = true;
        while (index != m&&flag) {
            int mx = 0;
            int mindex = 0;
            int st = index;
            for (int i = 0; i < n; i++) {
                int j = st;
                while (j<m&&v1[i] != v2[j]){
                    j++;
                }
                if (mx < j - index) {
                    mx = j - index;
                    mindex = j;
                }
            }
            if (mindex == 0)
                flag = false;
            cnt++;
            index = mindex;
        }
        if(flag)
            cout << cnt-1 << endl;
        else
            cout << -1 << endl;
    }
    return 0;
}