#include<bits/stdc++.h>
using namespace std;
using ll = long long;

#define fo(a,b) for(int a=0;a<(b);a++)

const int NMAX = 112345;

struct Nd
{
	vector<Nd *> e;
	int opon[2];
	int me[2];
} nd[NMAX];

pair<Nd *, int> qu[10*NMAX];
int qb, qe;


int n, m, f, t, s;

int main()
{
	scanf("%d%d%d%d%d", &n, &m, &f, &t, &s);
	fo(i,m)
	{
		int x,y;
		scanf("%d%d", &x, &y);
		nd[x].e.push_back(nd+y);
		nd[y].e.push_back(nd+x);
	}

	qb=qe=0;
	nd[t].opon[1] = 1;
	qu[qb++] = make_pair(nd+t, 1);
	while(qe!=qb)
	{
		Nd * c = qu[qe].first;
		int round = qu[qe].second + 1;
		qe++;
		for(Nd * to : c->e)
		{
			if(! to->opon[round%2])
			{
				to->opon[round%2] = round;
				qu[qb++] = make_pair(to, round);
			}
		}
	}

	fo(i,n) nd[i].e.push_back(nd+i);

	qb=qe=0;
	nd[s].me[1] = 1;
	qu[qb++] = make_pair(nd+s, 1);
	while(qe!=qb)
	{
		Nd * c = qu[qe].first;
		int round = qu[qe].second + 1;
		qe++;
		for(Nd * to : c->e)
		{
			if(! to->me[round%2] && (!to->opon[round%2] || to->opon[round%2]>round))
			{
				to->me[round%2] = round;
				qu[qb++] = make_pair(to, round);
			}
		}
	}
	if(!nd[f].me[0] && !nd[f].me[1])
		printf("death\n");
	else if(!nd[f].me[0])
		printf("%d\n", nd[f].me[1]-1);
	else if(!nd[f].me[1])
		printf("%d\n", nd[f].me[0]-1);
	else
		printf("%d\n", min(nd[f].me[0], nd[f].me[1])-1);
	return 0;
}