基础练习 高精度加法

 1 #include<iostream>
 2 #include<string>
 3 
 4 using namespace std;
 5 
 6 #define max(a,b) (a > b ? a : b)
 7 
 8 void add(string longString, string shortString, int* num3)
 9 {
10     int k = -1;
11     int longLen = longString.size();
12     int shortLen = shortString.size();
13 
14     for (int i = 1; i <= longLen; i++)
15     {
16         num3[i] = longString[longLen - i] - 48;
17     }
18     for (int i = 1; i <= shortLen; i++)
19     {
20         num3[i] += shortString[shortLen - i] - 48;
21     }
22 }
23 
24 int main()
25 {
26     string num1;
27     string num2;
28     int *num3 = new int[102];
29     int k = -1;
30 
31     cin >> num1;
32     cin >> num2;
33 
34     if (num1.size() >= num2.size()) //如果1长1作为长字符串
35     {
36         add(num1, num2, num3);
37     }
38     else
39     {
40         add(num2, num1, num3); //如果2长2作为长字符串
41     }
42     
43     int m = max(num1.size(), num2.size());
44     for (int i = 1; i <= m; i++)
45     {
46         if (num3[i] >= 10)
47         {
48             num3[i] -= 10;
49             ++num3[i + 1];
50         }
51     }
52 
53     if (num3[m + 1] > 0)
54     {
55         m++;
56     }
57 
58 
59     for (int i = m; i >= 1; i--)
60     {
61         cout << num3[i];
62     }
63 
64     return 0;
65 }