#include <cstdio>#include <cstring>using namespace std;const int N=200010,inf=~0U>>2,M=200000;int ans=-1,x,S,T,time[N],q[N],size,h,t,n,m,k,ed,dis[N],in[N],nxt[N],w[N],v[N],g[N],u,e,cost;void add(int x,int y,int z){v[++ed]=y;w[ed]=z;nxt[ed]=g[x];g[x]=ed;}bool spfa(int S,int limit){    for(int i=1;i<=n;i++)dis[i]=inf,in[i]=0,time[i]=0;    time[S]=1,dis[S]=0,in[S]=1;    int i,x,size; q[h=t=size=1]=S;    while(size){        for(i=g[x=q[h]],h=(h+1)%M,size--;i;i=nxt[i])if(dis[x]+(w[i]>limit?1:0)<dis[v[i]]){            dis[v[i]]=dis[x]+(w[i]>limit?1:0);            if(!in[v[i]]){                time[v[i]]++,t=(t+1)%M,size++,in[q[t]=v[i]]=1;                if(time[v[i]]>n)return 0;            }        }in[x]=0;    }return dis[T]<=k;}int main(){    scanf("%d%d%d",&n,&m,&k);    memset(v,0,sizeof(v)); memset(nxt,0,sizeof(nxt));    memset(w,0,sizeof(w)); memset(g,0,sizeof(g)); ed=0;    for(int i=1;i<=m;i++){        scanf("%d%d%d",&u,&e,&cost);        add(u,e,cost);add(e,u,cost);    }int l=0,r=1000000;T=n;    while(l<=r){        int mid=(l+r)>>1;        if(spfa(1,mid)){ans=mid;r=mid-1;}        else l=mid+1;    }return printf("%d\n",ans),0;}