【Water Problem】A+B problem (High-precision)

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cmath>
 4 #include<cstdlib>
 5 #include<cstring>
 6 #include<string>
 7 #include<queue>
 8 #include<deque>
 9 #include<stack>
10 #include<vector>
11 #include<algorithm>
12 #include<iomanip>
13 #define LL long long
14 #define MAXN 50001
15 #define P 123456
16 using namespace std;
17 int a[P],b[P],c[P],ka=1,kb=1;
18 char ca[P],cb[P];
19 int main()
20 {
21     scanf("%s%s",ca,cb);
22     int lena=strlen(ca),lenb=strlen(cb);
23     int j=1;
24     for(int i=lena-1;i>=0;i--)
25     {
26         a[ka]+=j*(ca[i]-‘0‘);
27         j*=10;
28         if(j==1000)
29             j=1,ka++;
30     }
31     
32     if(j!=1)
33         ka++,j=1;
34     for(int i=lenb-1;i>=0;i--)
35     {
36         b[kb]+=j*(cb[i]-‘0‘);
37         j*=10;
38         if(j==1000)
39             j=1,kb++;
40     }
41     if(j!=1)
42         kb++,j=1;
43     
44     //a[],b[] finish
45     
46     int e=0;
47     for(int i=1;i<=max(ka,kb);i++)
48     {
49         c[i]=(a[i]+b[i]+e)%1000;
50         e=(a[i]+b[i]+e)/1000;
51     }
52     int k=max(ka,kb)+1;
53     while(k>0&&!c[k]) k--;
54         printf("%d",c[k]);
55     for(int i=k-1;i>=1;i--)
56         printf("%03d",c[i]);
57     
58     return 0;
59 }