(数组的应用二：高精度运算4.2.1)POJ 1504 Adding Reversed Numbers(将一个数取反)

package com.njupt.acm;

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

public class POJ_1504 {

	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		
		int t = scanner.nextInt();
		while(t>0){
			String str1 = scanner.next();
			String str2 = scanner.next();
			
			//StringBuilder的reverse()方法能将一个字符串取反
			StringBuilder sb1 = new StringBuilder(str1);
			StringBuilder sb2 = new StringBuilder(str2);
			
		
			//Integer.parseInt(str)..能去掉前置的无效0
			int add1 = Integer.parseInt(sb1.reverse().toString()); 
			int add2 = Integer.parseInt(sb2.reverse().toString()); 
			
			int result = add1 + add2;
			
			String str3 = String.valueOf(result);
			StringBuilder sb3 = new StringBuilder(str3);
			System.out.println(Integer.parseInt(sb3.reverse().toString()));
			
			t--;
		}
		
	}
}