C :

#include <stdio.h>

long long int countLuckyNumber(long long int);

int main()
{
	long long int A, B, countAMinus1, countB;
	int T;
	
	while (EOF != scanf("%d", &T)){
		
		while (T--){
			scanf("%lld%lld", &A, &B);
			countB = countLuckyNumber(B);
			countAMinus1 = countLuckyNumber(A-1);
			printf("%lld\n", countB - countAMinus1);
		}
	}
	
	return 0;
}

long long int countLuckyNumber(long long int N)
{
	long long int countN, tmp;
	int sum, unitsN;
	
	if (N < 0){
		return 0;
	}
	
	countN = N / 10;
	tmp = countN;
	unitsN = N % 10;

	sum = 0;
	while (tmp){
		sum += tmp % 10;
		tmp /= 10;
	}
	
	sum %= 10;
	if (sum == 0){
		countN++;
	}else if(sum + unitsN >= 10){
		countN++;
	}
	
	return countN;
}