hdoj 1133 Buy the Ticket 【DP】【java】【水】

import java.util.Scanner;  import java.math.BigInteger;  public class Main {public static void main(String[] args){Scanner input = new Scanner(System.in);BigInteger[][]  flag = new BigInteger[101][101];BigInteger[] fac = new BigInteger[101];fac[0] = BigInteger.ONE;for(int i=1; i<101; i++)fac[i] = fac[i-1].multiply(BigInteger.valueOf(i));for(int m=0; m<101; m++)flag[0][m] = BigInteger.ONE;for(int n=1; n<101; n++)for(int m=0; m<101; m++)if(m < n)flag[n][m] = BigInteger.ZERO;elseflag[n][m] = flag[n][m-1].add(flag[n-1][m]);int cnt = 0;while(input.hasNext()){int m = input.nextInt();int n = input.nextInt();cnt++;if(m == 0 && n == 0)break;System.out.println("Test #"+cnt+":");System.out.println(flag[n][m].multiply(fac[n]).multiply(fac[m]));}}}