/*
ID: cmykrgb1
PROG: phoneline
LANG: C++
*/

#include <iostream>
#define MAX 1001
#define MAXP 10001
#define MAXL 1000000
using namespace std;

class tQueue
{
public:
	class linklist
	{
	public:
		linklist* next;
		int value;
		linklist()
		{
			next=0;
			value=0;
		}
	};
	linklist *first,*last;
	int size;
	bool inq[MAX];
	void add(int p)
	{
		if (size==0)
			first=last=new linklist;
		else
			last=last->next=new linklist;
		last->value=p;
		inq[p]=true;
		size++;
	}
	int del()
	{
		int rtn=first->value;
		inq[rtn]=false;
		linklist *tfirst=first;
		first=first->next;
		delete tfirst;
		size--;
		return rtn;
	}
	void reset()
	{
		size=0;
		first=last=0;
		memset(inq,0,sizeof(inq));
	}
	tQueue()
	{
		reset();
	}
};

class list
{
public:
	list *next;
	int p;
	list(int &tp)
	{
		p=tp;
		next=0;
	}
};

class tadjl
{
public:
	list *first,*last;
	tadjl()
	{
		first=last=0;
	}
	void ins(int p)
	{
		if (first)
			last=last->next=new list(p);
		else
			first=last=new list(p);
	}
};

tadjl adjl[MAX];
tQueue Q;
int dis[MAX][MAX],sp[MAX];
int N,P,K;

void init()
{
	int i,a,b,v;
	freopen("phoneline.in","r",stdin);
	freopen("phoneline.out","w",stdout);
	cin >> N >> P >> K;
	for (i=1;i<=P;i++)
	{
		scanf("%d%d%d",&a,&b,&v);
		adjl[a].ins(b);
		adjl[b].ins(a);
		dis[a][b]=dis[b][a]=v;
	}
}

bool check(int A)
{
	list *k;
	int i,j,v;
	Q.reset();
	Q.add(1);
	memset(sp,0xf,sizeof(sp));
	sp[1]=0;
	while (Q.size)
	{
		i=Q.del();
		for (k=adjl[i].first;k;k=k->next)
		{
			j=k->p;
			v=dis[i][j];
			if (v>A)
				v=1;
			else
				v=0;
			if (sp[i]+v<sp[j])
			{
				sp[j]=sp[i]+v;
				if (!Q.inq[j])
					Q.add(j);
			}
		}
	}
	return sp[N]<=K;
}

void solve()
{
	int a,b,m;
	a=0;
	b=MAXL;
	while (a<b)
	{
		m=(a+b)/2;
		if (check(m))
			b=m;
		else
			a=m+1;
	}
	if (a==MAXL)
		a=-1;
	cout << a << endl;
}

int main()
{
	init();
	solve();
	return 0;
}