/**
* Worg
*/
#include <stack>
#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;
FILE *fin = freopen("santa.in", "r", stdin);
FILE *fout = freopen("santa.out", "w", stdout);
const int MAX_N = 1 + 45000;
/*----------------------------*/ /** General stuff */
vector< int > graph[MAX_N];
int N, M;
int S, E, Q;
/*----------------------------*/ /** Must visit */
bool mustVisit[MAX_N], checked[MAX_N];
/*----------------------------*/ /** Biconnected components */
bool criticalNode[MAX_N];
int level[MAX_N], biconnectedDP[MAX_N];
stack< pair< int,int > > Stack;
vector< vector< int > > comps;
vector< int > criticals, aux;
/*----------------------------*/ /** Path */
bool good[MAX_N];
vector< int > path;
/*----------------------------*/
void noChance() {
printf("No chance\n"); exit(0);
}
void readData() {
scanf("%d%d", &N, &M);
for(int i = 1; i <= M; i++) {
int u, v; scanf("%d%d", &u, &v);
graph[u].push_back(v); graph[v].push_back(u);
}
scanf("%d%d%d", &S, &E, &Q);
}
void mustVisitDFS(int node = S) {
checked[node] = true;
if(node == E) {
mustVisit[node] = true; return;
}
for(vector< int >::iterator it = graph[node].begin(); it != graph[node].end(); it++) {
if(!checked[*it]) {
mustVisitDFS(*it);
mustVisit[node] |= mustVisit[*it];
}
}
}
void addComponent(pair< int,int > p) {
pair< int,int > now;
do {
now = Stack.top(); Stack.pop();
aux.push_back(now.first); aux.push_back(now.second);
}while(now != p);
sort(aux.begin(), aux.end());
aux.erase(unique(aux.begin(), aux.end()), aux.end());
comps.push_back(aux); aux.clear();
criticals.push_back(p.first);
}
void biconnectedDFS(int node = S, int father = 0) {
biconnectedDP[node] = level[node];
for(vector< int >::iterator it = graph[node].begin(); it != graph[node].end(); it++) {
if(!level[*it] && mustVisit[*it]) {
level[*it] = level[node] + 1;
Stack.push(make_pair(node, *it));
biconnectedDFS(*it, node);
if(biconnectedDP[*it] >= level[node]) {
addComponent(make_pair(node, *it));
criticalNode[node] = true;
}
}
}
bool already = false;
for(vector< int >::iterator it = graph[node].begin(); it != graph[node].end(); it++) {
if(mustVisit[*it]) {
if(*it == father && !already) {
already = true;
} else {
biconnectedDP[node] = min(biconnectedDP[node], biconnectedDP[*it]);
}
}
}
}
bool Find(vector< int > &vec, int value) {
for(vector< int >::iterator it = vec.begin(); it != vec.end(); it++) {
if(*it == value) {
return true;
}
}
return false;
}
void Orientate() {
if(comps.size() == 0) {noChance();}
if(!Find(comps[0], Q)) { /* if maxDamage is not in the first component, then we have to reverse the order of the components */
for(int i = 0, j = (int)comps.size() - 1; i < j; i++, j--) {
swap(comps[i], comps[j]); swap(criticals[i], criticals[j]);
}
}
if(!Find(comps[0], Q)) {
noChance();
}
criticals[0] = Q; /* we want to start from Q */
}
bool Back(int limit, int current, int node, int last, bool freeFinish) {
checked[node] = true;
path.push_back(node);
if(current == limit) {
if(freeFinish) {
return true;
} else if(node == last) {
return true;
}
} else {
for(vector< int >::iterator it = graph[node].begin(); it != graph[node].end(); it++) {
if(good[*it] && !checked[*it] && !(limit != current + 1 && *it == last) &&
Back(limit, current + 1, *it, last, freeFinish)) {
return true;
}
}
}
checked[node] = false;
path.pop_back();
return false;
}
void solveComponent(int index, int first, int last, bool freeFinish) {
for(vector< int >::iterator it = comps[index].begin(); it != comps[index].end(); it++) {
good[*it] = true; checked[*it] = false;
}
if(!good[first]) {
noChance();
}
if(!freeFinish && !good[last]) {
noChance();
}
bool ok = Back((int)comps[index].size(), 1, first, last, freeFinish);
for(vector<int >::iterator it = comps[index].begin(); it != comps[index].end(); it++) {
good[*it] = false;
}
if(!ok) {
noChance();
}
}
void getPath() {
for(int i = 0; i < (int)comps.size() - 1; i++) {
solveComponent(i, criticals[i], criticals[i + 1], false);
}
solveComponent((int)comps.size() - 1, criticals[(int)comps.size() - 1], 0, true);
}
void writeData() {
printf("%d\n", (int)path.size());
for(vector< int >::iterator it = path.begin(); it != path.end(); it++) {
printf("%d ", *it);
}
}
int main() {
readData();
mustVisitDFS();
if(!mustVisit[Q]) {
noChance();
}
level[S] = 1; biconnectedDFS();
Orientate(); /* maxDamage has to be in the first or the last biconnected component */
getPath();
writeData();
return 0;
}