#include <bits/stdc++.h>
usingnamespacestd;typedeflonglongLL;intmain(){intF,S,G,U,D;cin>>F>>S>>G>>U>>D;vector<LL>visit(F+1);queue<int>q;q.push(S);visit[S]=1;if(S==G){cout<<0;return0;}intmove=0;while(intcurSize=q.size()){move++;for(intsz=0;sz<curSize;sz++){intcur=q.front();q.pop();intdown=cur-D;intup=cur+U;if(down==G||up==G){cout<<move;return0;}if(up<=F&&!visit[up]){visit[up]=1;q.push(up);}if(down>0&&!visit[down]){visit[down]=1;q.push(down);}}}cout<<"use the stairs";}