#include <bits/stdc++.h>
using namespace std;
#define int long long
void read(int& x)
{
x=0;
char ch=getchar();
while(!isdigit(ch))
{
ch=getchar();
}
while(isdigit(ch))
{
x=(x<<1)+(x<<3)+(ch^48);
ch=getchar();
}
}
void write(int x)
{
if(x>=10)
{
write(x/10);
}
putchar(x%10^48);
}
const int maxn=4e5+5;
int n,m,S,B,F;
int head[maxn<<1];
struct EDGE
{
int to,val,nxt;
}edge[maxn<<1];
int ecnt;
void add(int u,int to,int val)
{
edge[++ecnt].to=to;
edge[ecnt].val=val;
edge[ecnt].nxt=head[u];
head[u]=ecnt;
}
int dis_to_F[maxn];
bool vis[maxn];
void dijkstra()
{
memset(dis_to_F,0x3f3f3f3f,sizeof dis_to_F);
priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > > que;
que.push(make_pair(0,F));
dis_to_F[F]=0;
while(!que.empty())
{
int u=que.top().second;
que.pop();
if(vis[u])continue;
vis[u]=1;
for(int i=head[u];i;i=edge[i].nxt)
{
int to=edge[i].to;
if(dis_to_F[to]>dis_to_F[u]+edge[i].val)
{
dis_to_F[to]=dis_to_F[u]+edge[i].val;
que.push(make_pair(dis_to_F[to],to));
}
}
}
}
int temp[maxn];
int temptop;
int path_list[maxn],pltop;
void dfs(int u)
{
path_list[++pltop]=u;
vis[u]=1;
if(u==F)
{
return;
}
temptop=0;
for(int i=head[u];i;i=edge[i].nxt)
{
int to=edge[i].to;
if(vis[to])continue;
if(dis_to_F[to]+edge[i].val==dis_to_F[u])
{
temp[++temptop]=to;
}
}
sort(temp+1,temp+temptop+1);
dfs(temp[1]);
}
int S_to_pth[maxn];
void dijkstra2()
{
memset(vis,0,sizeof vis);
memset(S_to_pth,0x3f3f3f3f,sizeof S_to_pth);
priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > > que;
que.push(make_pair(0,S));
S_to_pth[S]=0;
while(!que.empty())
{
int u=que.top().second;
que.pop();
if(vis[u])continue;
vis[u]=1;
for(int i=head[u];i;i=edge[i].nxt)
{
int to=edge[i].to;
if(S_to_pth[to]>S_to_pth[u]+edge[i].val)
{
S_to_pth[to]=S_to_pth[u]+edge[i].val;
que.push(make_pair(S_to_pth[to],to));
}
}
}
}
int B_to_pth[maxn];
void dijkstra3()
{
memset(vis,0,sizeof vis);
memset(B_to_pth,0x3f3f3f3f,sizeof B_to_pth);
priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > > que;
que.push(make_pair(0,B));
B_to_pth[B]=0;
while(!que.empty())
{
int u=que.top().second;
que.pop();
if(vis[u])continue;
vis[u]=1;
for(int i=head[u];i;i=edge[i].nxt)
{
int to=edge[i].to;
if(B_to_pth[to]>B_to_pth[u]+edge[i].val)
{
B_to_pth[to]=B_to_pth[u]+edge[i].val;
que.push(make_pair(B_to_pth[to],to));
}
}
}
}
signed main()
{
read(n);
read(m);
read(S);
read(B);
read(F);
int u,v,w;
for(int i=1;i<=m;i++)
{
read(u);
read(v);
read(w);
add(u,v,w);
add(v,u,w);
}
dijkstra();
memset(vis,0,sizeof vis);
dfs(S);
dijkstra2();
dijkstra3();
long double ans2=100000000000.0;
for(int i=1;i<=pltop;i++)
{
int node=path_list[i];
long double s=(long double)S_to_pth[node]/2.0;
long double b=(long double)B_to_pth[node]/3.0;
if(b<=s)
{
ans2=min(ans2,b+((long double)S_to_pth[node]-b*2.0)/5.0);
}
}
long double firtime=(long double)B_to_pth[S]/3.0;
long double ssum=firtime*2.0;
long double as=ssum/(3.0-2.0)+firtime;
if(as*2.0<(long double)dis_to_F[S])
{
ans2=min(ans2,as);
}
if(abs(ans2-100000000000.0)<=1e-9)
{
puts("YES");
long double ans1=((long double)dis_to_F[B]/3.0-(long double)dis_to_F[S]/2.0)*3.0;
stringstream stre;
stre<<fixed<<ans1;
string ans;
stre>>ans;
while(ans.size()>1&&(ans[ans.size()-1]=='0'||ans[ans.size()-1]=='.'))ans.pop_back();
cout<<ans;
}
else
{
puts("NO");
stringstream stre;
stre<<fixed<<ans2;
string ans;
stre>>ans;
while(ans.size()>1&&(ans[ans.size()-1]=='0'||ans[ans.size()-1]=='.'))ans.pop_back();
cout<<ans;
}
return 0;
}