URAL1036. Lucky Tickets

链接

dp[i][j] += dp[i-1][j-g];背包吧

数据太大了 还是JAVA好用

 1 import java.io.*;
 2 import java.math.*;
 3 import java.text.*;
 4 import java.util.*;
 5 public class Big {
 6     public static void main(String[] args)
 7     {
 8         Scanner cin = new Scanner (System.in);
 9         BigInteger[][] dp;
10         dp  = new BigInteger[55][1010];
11         int i,j,g,s,n;
12         n = cin.nextInt();
13         s = cin.nextInt();
14         for(i = 0;  i <= n ; i++)
15             for(j = 0 ;j <= s ; j++)
16                 dp[i][j] = BigInteger.valueOf(0);
17         if(s%2!=0||s/n/2>9)
18         {
19             System.out.println(0);
20         }
21         else
22         {
23             s/=2;
24             for(i = 0 ; i <= 9 ; i++)
25                 dp[1][i] = BigInteger.valueOf(1);
26             for(i = 2; i <= n ; i++)
27             {
28                 for(j = 0 ; j <= s ; j++)
29                 {
30                     for(g = 0 ; g <= 9 ; g++)
31                     {
32                         if(g>j) break;
33                         dp[i][j]  = dp[i][j].add(dp[i-1][j-g]);
34                     }
35                 }
36             }
37             BigInteger ans;
38             ans = dp[n][s].multiply(dp[n][s]);
39             System.out.println(ans);
40         }
41     }
42 
43 }
View Code

 

posted @ 2013-09-05 10:59  _雨  阅读(203)  评论(0)  编辑  收藏  举报