大整数求和算法java版

package com.text1;

import java.util.Scanner;

/*
 * 大整数求和算法
 */
public class SubBignum{
	public static void add(int[] a,int[] b) {
		int[] p;
		int m = 0;
		int n = 0;
		int flag = 0;
		//在初始分配结果p数组长度多与最长长度保存进位
		if (a.length >= b.length) {
			p = new int[a.length + 1];
			m = b.length;
			n = a.length + 1;
		}
		else {
			p = new int[b.length + 1];
			m = a.length;
			n = b.length + 1;
		}
		//同有位置的加法
		for (int i = 0; i < m; i++) {
			p[i] = (a[i] + b[i] + flag)%10;
			flag = (a[i] + b[i] + flag) / 10;
		}
		//多余位置的加法
		if (a.length >=b.length) {
			for (int i = m; i < a.length ; i++) {
				p[i] = (a[i] + flag) % 10;
				flag = (a[i] + flag) / 10;
			}
			if (flag != 0) {
				p[a.length] = flag;
				System.out.println( "结果长度：" + (a.length + 1) );
				for (int i = 0; i < a.length + 1; i++)
					System.out.print(p[i] + " ");
			}
			else {
				System.out.println( "结果长度：" + a.length  );
				for (int i = 0; i < a.length; i++)
					System.out.print(p[i] + " ");
			}

		}
		if (b.length > a.length) {
			for (int i = m; i < b.length; i++) {
				p[i] = (b[i] + flag) % 10;
				flag = (b[i] + flag) / 10;
			}
			if (flag != 0) {
				p[b.length] = flag;
				System.out.println( "结果长度：" + (b.length + 1));
				for (int i = 0; i < b.length + 1; i++)
					System.out.print( p[i] + " ");
			}
			else {
				System.out.println( "结果长度：" + b.length  );
				for (int i = 0; i < b.length ; i++)
					System.out.print(p[i] + " ");
			}
			
		}
		
	}
public static void main() {
	int alength = 0;
	int blength = 0;
	int []a;
	int []b;
	Scanner scaner=new Scanner(System.in);
	System.out.print( "输入长度alength:");
	alength=scaner.nextInt();
	a = new int[alength];
	for (int i = 0; i < alength; i++) {
		a[i]=scaner.nextInt();
	}
	System.out.print("输入长度blength:");
	blength=scaner.nextInt();
	b = new int[blength];
	for (int i = 0; i < blength; i++) {
		b[i]=scaner.nextInt();
	}
	add(a, b);
} }