#include <iostream>
#include <queue>
#include <algorithm>
#include <vector>

using namespace std;
#define X first
#define Y second

int board[1000001];

queue<int> q;
vector<int> dx;
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int f,g,s,u,d;
    int flag=0;
    cin >> f >> s >> g >> u >> d;
    if(s==g) {
        cout << 0;
        return 0;
    }
    dx.push_back(u);
    dx.push_back(d);
    fill(board,board+1000001,-1);
    q.push(s);
    board[s]=0;
    while(!q.empty()) {
        int cur=q.front();q.pop();
        for(int i=0; i<2; i++) {
            if(i==0) {
                int nx=cur+dx[i];
                if(nx>f) continue;
                if(board[nx]!=-1) continue;
                if(nx==g) {
                    cout << board[cur]+1;
                    flag=1;
                    return 0;
                }
                q.push(nx);
                board[nx]=board[cur]+1;
            } else {
                int nx=cur-dx[i];
                if(nx<1) continue;
                if(board[nx]!=-1) continue;
                if(nx==g) {
                    cout << board[cur]+1;
                    flag=1;
                    return 0;
                }
                q.push(nx);
                board[nx]=board[cur]+1;
            }

        }
    }
    if(flag==0) {
        cout << "use the stairs";
    }
}