C :

#include <stdio.h>

char metamorphosis[1000001];

int main(){
	
	int i, remainder, n;
	
	scanf("%d", &n);
	while (n--){
		
		scanf("%s", metamorphosis);
		remainder = 0;
		i = 0;
		while (metamorphosis[i]){
			
			remainder = (remainder * 10 + (int)(metamorphosis[i]-'0')) % 10003;
			i++;
		}
		
		printf("%d\n", remainder);
	}
	
	return 0;
}

C++ :

#include <stdio.h>
#include <string.h>
#define MAXN 1000010
char a[MAXN];
int main()
{
	int i , n , num , len;
	scanf("%d",&n);
	while(n--)
	{
		num = 0;
		scanf("%s",a);
		len = strlen(a);
		for( i = 0 ; i < len ; i++)
		{
			num = (num *10 + (int)(a[i]-'0')) % 10003;
		}
		printf("%d\n",num);
	}
	return 0;
}