Hdoj 1133 Buy the Ticket [catlan], hdoj1133

Hdoj 1133 Buy the Ticket [catlan], hdoj1133

Q: m people (50 yuan) and n people (100 yuan) are going to buy tickets. I didn't have a ticket office at the beginning. I asked the number of types that everyone can buy at the end.

This is also a classic question of the catlan number type.

We can regard them as trains in and out of the station, but because people are different, we have to ride m at last! * N!

The final mathematical expression is (C (m + n, n)-C (m + n, m + 1) * m! * N! = The result is (m! * N !) * (M + 1-n)/(m + 1)

Note: When m is less than n, 0 is output directly.

Code:

import java.util.Scanner;import java.math.*;public class Main{        public static void main(String[] args){        Scanner cin = new Scanner(System.in);        BigInteger[] s = new BigInteger[220];        s[1] = new BigInteger("1");        int i;        for(i = 2; i < 220; i ++){            BigInteger c = new BigInteger(((Integer)i).toString());            s[i] = new BigInteger("1");            s[i] = s[i-1].multiply(c);            //System.out.println(s[i]);        }        int n, m, v = 0;        while(cin.hasNext()){            m = cin.nextInt();            n = cin.nextInt();            if(n == 0&&m ==0) return;            v++;            System.out.println("Test #"+v+":");            if(m < n){                System.out.println("0"); continue;            }            BigInteger temp1 = new BigInteger(((Integer)(m+1-n)).toString());            BigInteger temp2 = new BigInteger(((Integer)(m+1)).toString());            BigInteger ans = s[n+m];            ans = ans.multiply(temp1);            ans = ans.divide(temp2);            System.out.println(ans);        }    }}

Question link: http://acm.hdu.edu.cn/showproblem.php? Pid = 1, 1133