game

#include<iostream>
#include<vector>
#include<map>
#include<algorithm>
#include<clocale>
#include<cmath>

using namespace std;

int a[10000001];

int main()
{
    int T1 , T2 , S1 , S2 , n , m;
    cin >> n >> m >> S1 >> S2 >> T1 >> T2;
    if(S1 < S2)
        swap(S1 , S2);
    if(T2 < T1)
    {
        T1 = n - T1;
        T2 = n - T2;
    }
    fill(a , a + 10000001, 10000001);
    a[T1] = 0;

    int i;

    if(T1 + S2 - S1 > 0)
        a[T1 + S2 - S1] = min(a[T1 + S2 - S1] , 2);
    else if(T1 + S2 + S2 - S1 <= n)
        a[T1 + S2 + S2 - S1] = min(a[T1 + S2 + S2 - S1] , 3);
    if(T2 + S1 - S2 > 0)
        a[T1 + S1 - S2] = min(a[T1 + S1 - S2] , 2);
    else if(T1 + S1 + S1 - S2 <= n)
        a[T1 + S1 + S1 - S2] = min(a[T1 + S1 + S1 - S2] , 3);

    for(i = 0 ;a[i] == 10000001; i++);

    for(i; i < T2; i++)
    {
        if(a[i] < 10000001)
        {
            a[i + S1] = min(a[i + S1] , a[i] + 1);
            a[i + S2] = min(a[i + S2] , a[i] + 1);
        }
    }
    if(a[T2] <= m)
        cout << a[T2];
    else
        cout << -1;
    return 0;
}