Vova and Train 1066/A

///http://codeforces.com/contest/1066/problem/A

#include <iostream>
using namespace std;
int main()
{
    int L, V, a, b;

    int Q;
    cin>>Q;
    for (int i=0; i<Q; i++)
    {
        cin>>L>>V>>a>>b;

        int x = L/V;

        int T = (b-a+1);
        int Tx = 0;

        if ( T >= V ) ///si es mas chico
        {
            Tx = T/V;

            int sobra = T%V; ///me sobran...
            int LPR = b - sobra; ///me paro en la ultima pos del rango de tam multiplo de V
            int falta = V - LPR%V; ///a esa ultima pos le faltan...

            if (sobra >= falta)
                Tx++;
        }
        else
        {
            if ( a <= b-(b%V) )
                Tx++;
        }
        cout<< x-Tx <<endl;
    }

    return 0;
}