大数加法

 1 import java.util.Scanner;
 2 
 3 public class bigNumberPlus {
 4     static char[] reverse(char[] ch){//字符反转，即123转为321
 5         int length = ch.length;
 6         char[] temp = new char[length];
 7         for(int i=0;i<length;i++){
 8             temp[length-1-i] = ch[i];            
 9         }
10         
11         
12         return temp;
13     }
14     static void plus(char[] chr1, char[] chr2){
15         int length = chr1.length>=chr2.length?chr1.length:chr2.length;
16         chr1 = reverse(chr1);
17         chr2 = reverse(chr2);
18         int [] result = new int [length];
19     
20         int gobit = 0;
21         for(int i=0;i<length;i++){ //如果一个数的位数已遍历完，剩下的位数由0代替
22             int a_number = i<chr1.length?(chr1[i]-48):0;
23             int b_number = i<chr2.length?(chr2[i]-48):0;
24             int temp = gobit + a_number+b_number;
25             if(temp>=10){
26                 result[i] = temp-10;
27                 gobit = 1;
28             }else{
29                 result[i] = temp;
30                 gobit = 0;
31             }
32         }
33         if(gobit>0)        //最高位进位的话就输出，没将进位保存在result数组中
34             System.out.print(gobit);
35         for(int i=length-1;i>=0;i--)
36             System.out.print(result[i]);
37     }
38     public static void main(String[] args) {
39         // TODO Auto-generated method stub
40         Scanner  sc = new Scanner(System.in);
41         char [] chr1 = sc.next().toCharArray();
42         char [] chr2 = sc.next().toCharArray();
43         plus(chr1, chr2);
44         
45     }
46 
47 }