高精度加法-526互联

#include <bits/stdc++.h>
using namespace std;

int a[10005], b[10005], c[10005];

int main()
{
   string sa, sb;
   //把大数用字符串读入
   cin >> sa;
   cin >> sb;
   //把字符串一一对应到数组存储
   int la = sa.size();
   reverse(sa.begin(), sa.end()); //为啥要翻转
   for (int i = 0; i < la; i++)
       a[i] = sa[i] - '0';

   int lb = sb.size();
   reverse(sb.begin(), sb.end());
   for (int i = 0; i < lb; i++)
       b[i] = sb[i] - '0';

   int len = max(la, lb); //数组运算的位数取决于长的那个数组长度

   for (int i = 0; i < len; i++)//按位相加
       c[i] = a[i] + b[i];

   int jw = 0;//考虑进位
   for (int i = 0; i < len; i++)
   {
       c[i] += jw;
       jw = c[i] / 10;
       c[i] %= 10;
   }
   if (jw) c[len] = 1; //len是实际反向输出的最高位，最地位的下标0。
   else len--;

   //反向输出答案
   for (int i = len; i >= 0; i--)
       cout << c[i];
   return 0;
}