hdu3787(a+b)

http://acm.hdu.edu.cn/showproblem.php?pid=3787

#include"iostream"
using namespace std;
int main()
{
    char a[1001],b[1001];
    int c[1001],d[1001];
    int i;
    while(cin>>a>>b)
    {
        int L1=strlen(a);
        int L2=strlen(b);
        int start_a=1 , start_b=1;

        int s=0,t=0;

        for(i=0;i<L1;i++) if(a[i]>='0'&&a[i]<='9') c[s++]=a[i]-'0';
            for(i=0;i<L2;i++) if(b[i]>='0'&&b[i]<='9') d[t++]=b[i]-'0';

        if(a[0]=='-') start_a=-1; 
        if(b[0]=='-') start_b=-1;

        int sum_a=0,sum_b=0;

        for(i=0;i<s;i++)
        {
          sum_a+=c[i];
          if(i<s-1) sum_a*=10;
        }

        for(i=0;i<t;i++)
        {
          sum_b+=d[i];
          if(i<t-1) sum_b*=10;
        }

        cout<<start_a*sum_a+start_b*sum_b<<endl;

    }
    return 0;
}