def f(n):
    dp = [[[0,0] for _ in range(10)] for _ in range(20)]
    dp[-1][0][0]=1
    for i in range(19, 0, -1):
        d = n//(10**(i-1))%10
        left = 0
        left2 = 0
        tmp = 0
        for k in range(10):
            dp[i-1][k][1]+=dp[i][k][1]*(k+1)+left
            left += dp[i][k][1]
            # for j in range(10):
            #     dp[i-1][max(j,k)][1]+=dp[i][j][1]
            dp[i-1][k][1]+=dp[i][k][0]*tmp
            if k<d:
                # 元より入れたやつのが大きい
                left2 += dp[i][k][0]
                dp[i-1][k][1]+=left2
                tmp += 1
                # for j in range(k+1,10):
                #     dp[i-1][j][1]+=dp[i][j][0]
            
        for j in range(10):
            dp[i-1][max(j,d)][0]+=dp[i][j][0]
    res = 0
    for i in range(10):
        res += i*sum(dp[0][i])
    return res

T=int(input())
for _ in range(T):
    L,R=map(int,input().split())
    print(f(R) - f(L-1))