A+B problem (High-precision)

The "A+B problem" is very easy,but I failed for many times.

The code:

 #include<iostream>
 #include<cstdio>
 #include<cmath>
 #include<cstdlib>
 #include<cstring>
 #include<string>
 #include<queue>
 #include<deque>
 #include<stack>
 #include<vector>
 #include<algorithm>
 #include<iomanip>
 #define LL long long
 #define MAXN 50001
 #define P 123456
 using namespace std;
 int a[P],b[P],c[P],ka=,kb=;
 char ca[P],cb[P];
 int main()
 {
     scanf("%s%s",ca,cb);
     int lena=strlen(ca),lenb=strlen(cb);
     int j=;
     for(int i=lena-;i>=;i--)
     {
         a[ka]+=j*(ca[i]-'');
         j*=;
         if(j==)
             j=,ka++;
     }

     if(j!=)
         ka++,j=;
     for(int i=lenb-;i>=;i--)
     {
         b[kb]+=j*(cb[i]-'');
         j*=;
         if(j==)
             j=,kb++;
     }
     if(j!=)
         kb++,j=;

     //a[],b[] finish

     int e=;
     for(int i=;i<=max(ka,kb);i++)
     {
         c[i]=(a[i]+b[i]+e)%;
         e=(a[i]+b[i]+e)/;
     }
     int k=max(ka,kb)+;
     while(k>&&!c[k]) k--;
         printf("%d",c[k]);
     for(int i=k-;i>=;i--)
         printf("%03d",c[i]);

     return ;
 }

I have forgot to plus the "e" first, so I have so much mistake!!!