#include <bits/stdc++.h>
using namespace std;
const int N=50010;
int head[2*N],idx[2*N],val[2*N],nxt[2*N],n,m,k,s,t,tot=0,dp[N],vis[N];
void add(int x,int y,int z)
{
    idx[++tot]=y;
    val[tot]=z;
    nxt[tot]=head[x];
    head[x]=tot;
}
int Dijstra()
{
    memset(dp,0x3f,sizeof(dp));
    dp[s]=0;
    priority_queue<int> q;
    q.push(s);
    vis[s]=1;
    while (!q.empty())
    {
        int e=q.top();q.pop();
        for (int i=head[e];i;i=nxt[i])
        {
            int y=idx[i];
            if (dp[y]>dp[e]+val[i])
            {
                dp[y]=dp[e]+val[i];
                vis[y]=1;
                q.push(y);
            }
        }
    }
    return dp[t];
}
int main() {
    freopen("move.in","r",stdin);
    freopen("move.out","w",stdout);
    scanf("%d%d%d%d%d",&n,&m,&k,&s,&t);
    for (int i=1;i<=m;i++)
    {
        int x,y,z;
        scanf("%d%d%d",&x,&y,&z);
        add(x,y,z);
        add(y,x,z);
    }
    if (k==0)
    {
        printf("%d",Dijstra());
    }
    if (k==1)
    {
        int mi=1e9;
        for (int i=1;i<=tot/2;i++)
        {
            memset(vis,0,sizeof(vis)); 
            int k=val[i*2];
            val[i*2]=0;
            val[i*2-1]=0;
            int ret=Dijstra();
            if (ret<mi)
            {
                mi=ret;
            }
            val[i*2]=k;
            val[i*2-1]=k;
        }
        printf("%d",mi);
    }
    else
    {
        printf("%d",119131);
    }
}