#include <bits/stdc++.h> using namespace std; #define int long long #define rep(i, n) for (int i = 0; i < n; i++) int run(int x){ int cur = 0; while(x > 0) { int d = x%10; cur += d; x/=10; } return cur; } signed main(){ int q; cin >> q; while(q--) { int l, r; cin >> l >> r; int cnt= 0; for (int i = l; i <= r; i++) { cnt += run(i); } cout << cnt << endl; } return 0; }