例题9-1(uva-1025)

#include <iostream>
#include <istream>
#include <sstream>
#include <vector>
#include <stack>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <cstring>
#include <unordered_map>
#include <unordered_set>
#include <algorithm>
#include <numeric>
#include <chrono>
#include <ctime>
#include <cmath>
#include <cctype>
#include <string>
#include <cstdio>
#include <iomanip>


#include <thread>
#include <mutex>
#include <condition_variable>
#include <functional>
#include <iterator>
using namespace std;
const int maxn = 256, maxm = 56,INF = 1e9 + 7;
int nx[maxm], dp[maxn][maxm],  have[maxn][maxm][2],n;
//马的 换个顺序 就是错的 不知道原因  眼睛都找瞎了
//int dp[maxn][maxm],nx[maxm],   have[maxn][maxm][2],n;
int main()
{
	int m,t,tmp,kCase = 0;
	while (cin >> n && n) {
		memset(have, 0, sizeof(have));
		cin >> t;
		for (int i = 1; i < n; i++) cin >> nx[i];
		cin >> m;
		for (int i = 1; i <= m; i++) {
			cin >> tmp;
			have[tmp][1][0] = 1;
			for (int j = 2; j <= n; j++) {
				tmp += nx[j - 1];
				have[tmp][j][0] = 1;
			}
		}

		cin >> m;
		for (int i = 1; i <= m; i++) {
			cin >> tmp;
			have[tmp][n][1] = 1;
			for (int j = n - 1; j >= 1; j--) {
				tmp += nx[j];
				have[tmp][j][1] = 1;
			}
		}
	
		for (int i = 1; i < n; i++) dp[t][i] = INF;
		dp[t][n] = 0;

		for (int i = t - 1; i >= 0; i--) {
			for (int j = 1; j <= n; j++) {
				dp[i][j] = dp[i + 1][j] + 1;
				if (have[i][j][0] && j < n && i + nx[j] <= t) {
					dp[i][j] = min(dp[i][j], dp[i + nx[j]][j + 1]);
				}

				if (have[i][j][1] && j > 1 && i + nx[j - 1] <= t) {
					dp[i][j] = min(dp[i][j], dp[i + nx[j - 1]][j - 1]);
				}
			}
		}
		cout << "Case Number " << ++kCase << ": ";
		if (dp[0][1] >= INF) cout << "impossible" << endl;
		else cout << dp[0][1] << endl;
	}
	return 0;
}