#include <cstdio>

#include <cstring>

int Tim, num[20];

long long M[5][20];

long long run(int x, int cnt, int lim) {

	if (cnt > 3) return 0;

	if (!x) return 1;

	if ((~M[cnt][x]) && !lim) return M[cnt][x];

	long long ans = 0;

	for (int op = lim, i = lim ? num[x] : 9; ~i; i--, op = 0) {

		ans += run(x - 1, cnt + bool(i), op);

	}

	if (!lim) M[cnt][x] = ans;

	return ans;

}

long long solve(long long x) {

	int len = 0;

	while (x) {

		num[++len] = x % 10;

		x /= 10;

	}

	return run(len, 0, 1);

}

int main() {

	scanf("%d", &Tim);

	memset(M, -1, sizeof M);

	while (Tim --> 0) {

		long long l, r;

		scanf("%lld%lld", &l, &r);

		printf("%lld\n", solve(r) - solve(l - 1));

	}

	return 0;

}