java寫acm類名必須為Main
第1000題

import java.util.Scanner;
public class Main {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner s = new Scanner(System.in);
        while (s.hasNextInt()) {
            int a = s.nextInt();
            int
 
 b = s.nextInt();
            System.out.println(a + b);
        }
    }
}

第1001題

import java.util.Scanner;

public class Main {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner s = new Scanner(System.in);
        while
 
 (s.hasNextInt()) {
            int n = s.nextInt();
            int sum = 0;
            for (int i = 0; i <= n; i++) {
                sum = sum + i;
            }
            System.out.println(sum);
            System.out.println();
        }
    }
}

第1002題

import java.math.BigInteger;
import java.util.Scanner;

public
 
 class Main {

    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        int t = s.nextInt();
        for (int i = 0; i < t; i++) {
            BigInteger a = s.nextBigInteger();
            BigInteger b = s.nextBigInteger();
            System.out.println("Case" + " " + +(i + 1) + ":");
            System.out.println(a + " + " + b + " = " + a.add(b));
            if (i != t - 1) {
                System.out.println();
            }
        }
    }
}