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#include<bits/stdc++.h>
using namespace std;const int N=1e3+10,M=2e4+10;
typedef pair<int,int> PII;
int n,p,k;
int h[N],ne[M],w[M],idx,e[M];
int dist[N];
bool st[N];void add(int a,int b,int l)
{e[idx]=b,ne[idx]=h[a],w[idx]=l,h[a]=idx++;
}bool check(int limit)
{memset(dist,0x3f,sizeof dist);memset(st,0,sizeof st);dist[1]=0;priority_queue<PII,vector<PII>,greater<PII>> heap;heap.push({dist[1],1});while(!heap.empty()){auto t=heap.top();heap.pop();int ver=t.second;if(st[ver]) continue;st[ver]=true;for(int i=h[ver];i!=-1;i=ne[i]){int j=e[i];int cost=(w[i]>limit ? 1 : 0);if(dist[j]>dist[ver]+cost){dist[j]=dist[ver]+cost;heap.push({dist[j],j});}}}return dist[n]<=k;
}int main()
{memset(h,-1,sizeof h);ios::sync_with_stdio(0),cin.tie(0);cin>>n>>p>>k;int max_fee=0;for(int i=1;i<=p;i++){int a,b,l;cin>>a>>b>>l;add(a,b,l),add(b,a,l);max_fee=max(max_fee,l);}int ans=-1;int l=0,r=max_fee;while(l<=r){int mid=l+(r-l)/2;if(check(mid)){r=mid-1;ans=mid;}else{l=mid+1;}}cout<<ans<<endl;
}