大数相加

//大数相加,这两天就搞大数了,呼呼,优化的还行

public class BIG {
public static void main(String[] args) {
String a = "12345678988555111";
String b = "99945684641111";
BigAdd bigAdd = new BigAdd();
int[] add = bigAdd.add(a,b);
for (int i : add) {
System.out.print(i);
}
}
}
class BigAdd{
public int[] add(String a,String b){
int jw = 0,num1,num2;//jw:进位
String addZero = "0";
int la = a.length();
int lb = b.length();
int l = la>lb?la:lb;//记录较长的数的长度l,确定结果数组长度
int[] arr = new int[l+1];//数组长度:两个数相加的最大长度l+1
//短数高位补0使位数相同
for (int i = 0; i < Math.abs(la-lb); i++) {
if(la>lb){
b = addZero + b;
}else if(la<lb){
a = addZero + a;
}
}
//共l次循环,对应位相加,结果从arr[l]赋到a[1].
for (int i = l-1; i >= 0; i--) {
num1 = a.charAt(i)-'0';
num2 = b.charAt(i)-'0';
arr[i+1] = (num1+num2+jw)>9?num1+num2+jw-10:num1+num2+jw;
jw = num1+num2+jw>9?1:0;
}
//a[0]为最高位,为0或1.
arr[0] = jw==1?1:0;
return arr;
}
}