#include <bits/stdc++.h> using namespace std; #define int long long signed main() { int n; cin >> n; for (int i = 0; i < n; i++) { int a, b; cin >> a >> b; int ans = (b - a)/9 * 45; for (int i = a + (b - a)/9 * 9; i <= b; i++) { ans += (i%9 == 0 ? 9 : i%9); } cout << ans << "\n"; } return 0; }