UVa 424 Integer Inquiry

import java.math.BigInteger;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner cin = new Scanner(System.in);
BigInteger sum, a;
sum = BigInteger.ZERO;
while(cin.hasNext()){
a = cin.nextBigInteger();
if(a.equals(BigInteger.ZERO)){
break;
}
sum = sum.add(a);
}
System.out.println(sum);
}

}

#include<stdio.h>
#include<string.h>
#include<stdlib.h>

char s[105];
int num[105];

int main()
{
memset(num,0,sizeof(num));
while(scanf("%s",s) != EOF)
{
if(s[0] == '0') break;
int len = strlen(s);
for(int i = 0; i < len; i++)
{
num[i] += s[len-1-i] - '0';
if(num[i] > 9)
{
num[i] = num[i]%10;
num[i+1] += 1;
}
}
}
int i;
for(i = 105; i >= 0; i--)
if(num[i]) break;
for(int j = i; j >= 0; j--)
printf("%d",num[j]);
printf("\n");
return 0;
}