poj1000

A+B

//Memory Time 
//2996K 750MS
import java.io.*;
import java.util.*;
public class Main
{
    public static void main(String args[]) throws Exception
    {
        Scanner cin=new Scanner(System.in);
        int a=cin.nextInt(),b=cin.nextInt();
        System.out.println(a+b);
    }
}                    

在输入输出为int型范围（-2147483648 到2147483647）  计算正常，否则

Exception in thread "main" java.util.InputMismatchException: For input string: "1234567984564313221"
at java.util.Scanner.nextInt(Scanner.java:2123)
at java.util.Scanner.nextInt(Scanner.java:2076)
at Main.main(Main.java:10)

实现超大数字的A+B代码如下：

import java.io.*;
import java.util.*;
import java.lang.String;
import java.math.BigDecimal;
public class Main
{
    public static void main(String args[]) throws Exception
    {
        String s1,s2;
        Scanner cin=new Scanner(System.in);
        s1 = cin.next();
        s2 = cin.next();
        BigDecimal b1 = new BigDecimal(s1);
        BigDecimal b2 = new BigDecimal(s2);
        System.out.println(b1.add(b2));
        cin.close();
    }
}        

测试：

123456789456789
12345678914561
135802468371350