// #pragma GCC optimize("Ofast,unroll-loops")
#include "bits/stdc++.h"
using namespace std;
#ifdef duc_debug
#include "bits/debug.h"
#else
#define debug(...)
#endif
#define int long long
int l, r;
void solve(){
cin >> l >> r;
int x = r / 9 * 9 + (l%9);
if(x > r) x -= 9;
int ans = 45 * (max(0LL, x - l) / 9);
debug(ans);
int re = (l - 1) % 9, rem = (r - 1) % 9;
if(re > rem) rem += 9;
for(int i = re; i <= rem; i++){
ans += (i % 9) + 1;
debug(i, ans);
}
debug(ans);
cout << ans << '\n';
}
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
int test = 1;
cin >> test;
for(int i=1;i<=test;i++){
// cout << "Case " << "#" << i << ": ";
solve();
}
return 0;
}
