NYOJ 大数类总结（java）

棋盘覆盖

题目链接：​​http://acm.nyist.net/JudgeOnline/problem.php?pid=45​​

样例输入

3 1 2 3

样例输出

1 5 21

代码如下：

import java.io.*;
import java.util.*;
import java.math.BigDecimal;
import java.math.BigInteger;//声明BigInteger大数类
public class Main
{
    public static void main(String args[])
    {
        Scanner cin = new Scanner(System.in);
        int t=cin.nextInt();
        while(t-->0)
        {
            int n;
            n=cin.nextInt();
            BigInteger a=BigInteger.valueOf(4);
            for(int i=1; i<n; ++i)
                a=a.multiply(BigInteger.valueOf(4));
            System.out.println(a.subtract(BigInteger.valueOf(1)).divide(BigInteger.valueOf(3)));
        }
    }
}

比较大小

题目链接：​​http://acm.nyist.net/JudgeOnline/problem.php?pid=73​​

样例输入

111111111111111111111111111 88888888888888888888 -1111111111111111111111111 22222222 0 0

样例输出

a>b a<b

代码如下：

import java.io.*;
import java.util.*;
import java.math.BigDecimal;
import java.math.BigInteger;//声明BigInteger大数类
public class Main
{
    public static void main(String args[])
    {
        Scanner cin = new Scanner(System.in);
        while(cin.hasNext())
        {
            BigInteger a=cin.nextBigInteger();
            BigInteger b=cin.nextBigInteger();
            BigInteger zero=BigInteger.ZERO;
            if(a.compareTo(zero)==0&&b.compareTo(zero)==0) break;
            int f=a.compareTo(b);
            if(f==-1)
                System.out.println("a<b");
            else if(f==0)
                System.out.println("a==b");
            else 
                System.out.println("a>b");
        }
    }
}

递推求值

题目链接：​​http://acm.nyist.net/JudgeOnline/problem.php?pid=114​​

样例输入

1 1 1

样例输出

69087442470169316923566147

代码如下：

import java.io.*;
import java.util.*;
import java.math.BigDecimal;
import java.math.BigInteger;//声明BigInteger大数类
public class Main
{
    public static void main(String args[])
    {
        Scanner cin = new Scanner(System.in);
        BigInteger fac[]=new BigInteger[100];
        while(cin.hasNext())
        {
            for(int i=0; i<=2; ++i)
                fac[i]=cin.nextBigInteger();
            for(int i=3; i<=99; ++i)
                fac[i]=fac[i-1].add(fac[i-2]).add(fac[i-3]);
            System.out.println(fac[99]);
        }
    }
}