uva 10106 Product

忽略了零的时候的情况啊！！！
题目连接http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=1047


#include<stdio.h>
#include<math.h>
#include<string.h>
char a[300],b[300];
int f[600],count;


int main()
{
    while(scanf("%s%s",a,b) == 2)
    {
        int len1,len2,i,j,m,max,wei,k;
        len1 = strlen(a);
        len2 = strlen(b);
        
        for(i = 0;i < 600-1;i++)
            f[i] = 0;
        for(i = len2-1;i >= 0;i--)
        {            
            
            count = len2-i-1;
            m = wei = 0;
            for(j = len1-1;j >= 0;j--)
            {
                m = (a[j]-'0')*(b[i]-'0')+f[count]+wei;
                f[count++] = m%10;
                wei = m/10;
            }

            if(wei)
                f[count++] = wei;
        }

        for(i = count-1;i >0 ;i--)
        {
            if(f[i])
                break;
        }
        for(;i >= 0;i--)
            printf("%d",f[i]);
        puts("");

    }
    return 0;
}