Yet_another_SOD_problem.cpp

#include <bits/stdc++.h>
using namespace std;
#define ll long long
int main()
{
    ll t;
    cin >> t;
    while (t--)
    {
        ll l, r;
        cin >> l >> r;
        cout << r / 3 - (l - 1) / 3 << endl;
    }
    return 0;
}