Uva 10106 Product

#include<stdio.h>
#include<string.h>
char a[1000],b[1000];
int sum[1000];

int main(void)
{
memset(a,0,sizeof(a));
memset(b,0,sizeof(b));
int i, j;
while(scanf("%s%s",a,b) == 2)
{
memset(sum,0,sizeof(sum));
for(i =0,j= strlen(a)-1;i < j;i++,j--)
{
int temp = a[i];a[i] = a[j] ;a[j] = temp;
}
for(i =0,j= strlen(b)-1;i < j;i++,j--)
{
int temp = b[i];b[i] = b[j] ;b[j] = temp;
}
int count = 0;
for(i = 0;i< strlen(a);i++)
{
count = 0;
for(j = 0;j <strlen(b);j++)
{
int temp = (a[i]-48)*(b[j]-48) + count +sum[i+j];
sum[i+j] = temp%10;
count = temp/10;
}
sum[i+j] = count;
}
for(i = 999;i>0;i--) if(sum[i]) break;
for(j = i;j >= 0;j--) printf("%d",sum[j]);
printf("/n");
}
return 0;
}