http://www.verejava.com/?id=17159675312132

import java.math.BigDecimal;
import java.math.BigInteger;

public class Test {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // 計算 1 到 30 的相乘的結果
        BigInteger sum=new BigInteger("1");
        for(int i=1;i<=30;i++)
        {
            sum=sum.multiply(new BigInteger(String.valueOf(i)));
        }
        System.out.println(sum);
        
        BigInteger bi1=new BigInteger("20000000002000000002");
        BigInteger bi2=new BigInteger("40000000004000000004");
        System.out.println(bi1.add(bi2));
        System.out.println(bi2.subtract(bi1));
        System.out.println(bi1.divide(new BigInteger("2")));
        
        BigDecimal bd1=new BigDecimal("20000000002000000000.0000000002");
        BigDecimal bd2=new BigDecimal("30000000003000000000.0000000003");
        System.out.println(bd1.add(bd2));
        System.out.println(bd2.subtract(bd1));
        System.out.println(bd2.divide(new BigDecimal("2")));
        System.out.println(bd2.multiply(new BigDecimal("2")));
        
    }
}

 

http://www.verejava.com/?id=17159675312132

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