大数加法 待完善

//邵文政20142894
import javax.swing.JOptionPane;
public class Bigintjiajian {
public static void main(String[]args)
{ int length1,length2,j,k,a=0,e=0;
String aa=new String();
String firstnumber=JOptionPane.showInputDialog("请输入第一个大数");
String secondnumber=JOptionPane.showInputDialog("请输入第二个大数");
length1=firstnumber.length();
length2=secondnumber.length();
if(length1>length2)
{
a=length1;
}
else
{
a=length2;
firstnumber=aa;
firstnumber=secondnumber;
secondnumber=aa;

}
char number[] =new char [a];
char number1[]=new char [a];
char number2[]=new char [a];
e=a;
for(int i=secondnumber.length();i>0;i--)
{
number[a-1]=secondnumber.charAt(i-1);
a--;
}
for(int i=0;number[i]!=0;i++)
{
number[i]=‘0‘;
}
for(int i=firstnumber.length();i>0;i--)
{
number1[e-1]=firstnumber.charAt(i-1);
e--;
}
for(int i=firstnumber.length();i>0;i--)
{
number2[i-1]=(char)(number[i-1]+number1[i-1]);
if(number2[i-1]>=10)
{
number2[i-1]=(char) (number2[i]%10);
j=number2[i-1]/10;
number2[i-2]=(char) (number2[i-2]+j);
}
}
String message="0";
for(int i=0;i<firstnumber.length();i++)
{

message=message+" "+number2[i];
}
String title="计算结果";
JOptionPane.showConfirmDialog(null,
message, title,JOptionPane.CLOSED_OPTION);


}

}

大数加法 待完善

原文：http://www.cnblogs.com/aishangtaxuefeihong/p/4931551.html