#include<bits/stdc++.h>
using namespace std;

#define REP(i,a,b) for(i=a;i<b;i++)
#define rep(i,n) REP(i,0,n)

#define mygc(c) (c)=getchar_unlocked()
#define mypc(c) putchar_unlocked(c)

#define ll long long
#define ull unsigned ll

void reader(int *x){int k,m=0;*x=0;for(;;){mygc(k);if(k=='-'){m=1;break;}if('0'<=k&&k<='9'){*x=k-'0';break;}}for(;;){mygc(k);if(k<'0'||k>'9')break;*x=(*x)*10+k-'0';}if(m)(*x)=-(*x);}
void reader(ll *x){int k,m=0;*x=0;for(;;){mygc(k);if(k=='-'){m=1;break;}if('0'<=k&&k<='9'){*x=k-'0';break;}}for(;;){mygc(k);if(k<'0'||k>'9')break;*x=(*x)*10+k-'0';}if(m)(*x)=-(*x);}
int reader(char c[]){int i,s=0;for(;;){mygc(i);if(i!=' '&&i!='\n'&&i!='\r'&&i!='\t'&&i!=EOF) break;}c[s++]=i;for(;;){mygc(i);if(i==' '||i=='\n'||i=='\r'||i=='\t'||i==EOF) break;c[s++]=i;}c[s]='\0';return s;}
template <class T, class S> void reader(T *x, S *y){reader(x);reader(y);}
template <class T, class S, class U> void reader(T *x, S *y, U *z){reader(x);reader(y);reader(z);}
template <class T, class S, class U, class V> void reader(T *x, S *y, U *z, V *w){reader(x);reader(y);reader(z);reader(w);}

void writer(int x, char c){int s=0,m=0;char f[10];if(x<0)m=1,x=-x;while(x)f[s++]=x%10,x/=10;if(!s)f[s++]=0;if(m)mypc('-');while(s--)mypc(f[s]+'0');mypc(c);}
void writer(ll x, char c){int s=0,m=0;char f[20];if(x<0)m=1,x=-x;while(x)f[s++]=x%10,x/=10;if(!s)f[s++]=0;if(m)mypc('-');while(s--)mypc(f[s]+'0');mypc(c);}
void writer(const char c[]){int i;for(i=0;c[i]!='\0';i++)mypc(c[i]);}
void writer(const char x[], char c){int i;for(i=0;x[i]!='\0';i++)mypc(x[i]);mypc(c);}
template<class T> void writerLn(T x){writer(x,'\n');}
template<class T, class S> void writerLn(T x, S y){writer(x,' ');writer(y,'\n');}
template<class T, class S, class U> void writerLn(T x, S y, U z){writer(x,' ');writer(y,' ');writer(z,'\n');}
template<class T> void writerArr(T x[], int n){int i;if(!n){mypc('\n');return;}rep(i,n-1)writer(x[i],' ');writer(x[n-1],'\n');}

template<class T> void* setUndirectEdge(int N, int M, int A[], int B[], T C[], int **es, int ***edge, T ***cost, void *workMemory){int i;*es=(int*)workMemory;*edge=(int**)((*es)+N);(*edge)[0]=(int*)((*edge)+N);rep(i,N)(*es)[i]=0;rep(i,M)(*es)[A[i]]++,(*es)[B[i]]++;REP(i,1,N)(*edge)[i]=(*edge)[i-1]+(*es)[i-1];(*cost)=(T**)((*edge)[N-1]+(*es)[N-1]);(*cost)[0]=(T*)((*cost)+N);REP(i,1,N)(*cost)[i]=(*cost)[i-1]+(*es)[i-1];workMemory=(void*)((*cost)[N-1]+(*es)[N-1]);rep(i,N)(*es)[i]=0;rep(i,M)(*edge)[A[i]][(*es)[A[i]]]=B[i],(*cost)[A[i]][(*es)[A[i]]++]=C[i],(*edge)[B[i]][(*es)[B[i]]]=A[i],(*cost)[B[i]][(*es)[B[i]]++]=C[i];return workMemory;}

template<class T> void sort(int N, T a[], void *mem = NULL){sort(a,a+N);}
template<class T1, class T2> void sort(int N, T1 a[], T2 b[], void *mem){int i;pair<T1,T2> *r=(pair<T1, T2>*)mem;rep(i,N)r[i].first=a[i],r[i].second=b[i];sort(r,r+N);rep(i,N)a[i]=r[i].first,b[i]=r[i].second;}
template<class T1, class T2, class T3> void sort(int N, T1 a[], T2 b[], T3 c[], void *mem){int i;pair<T1,pair<T2,T3> > *r=(pair<T1,pair<T2,T3> >*)mem;rep(i,N)r[i].first=a[i],r[i].second.first=b[i],r[i].second.second=c[i];sort(r,r+N);rep(i,N)a[i]=r[i].first,b[i]=r[i].second.first,c[i]=r[i].second.second;}
template<class T1, class T2, class T3, class T4> void sort(int N, T1 a[], T2 b[], T3 c[], T4 d[], void *mem){int i;pair<pair<T1,T2>,pair<T3,T4> > *r=(pair<pair<T1,T2>,pair<T3,T4> >*)mem;rep(i,N)r[i].first.first=a[i],r[i].first.second=b[i],r[i].second.first=c[i],r[i].second.second=d[i];sort(r,r+N);rep(i,N)a[i]=r[i].first.first,b[i]=r[i].first.second,c[i]=r[i].second.first,d[i]=r[i].second.second;}

void unionInit(int d[],int s){int i;rep(i,s)d[i]=i;}
int unionGet(int d[],int n){int t=n,k;while(d[t]!=t)t=d[t];while(d[n]!=n)k=d[n],d[n]=t,n=k;return n;}
int unionConnect(int d[],int a,int b){a=unionGet(d,a);b=unionGet(d,b);if(a==b)return 0;d[a]=b;return 1;}

#define INF 1000000000

int N, M, T;
int A[10000], B[10000], C[10000];
int mat[99][99];
int V[1000], use[1000];
int *es, **edge, **cost;


int prefield(){
  const int n = N;
  const int numT = T;
  if (numT <= 1) return 0;

  static int OPT[(1 << 15)][38];
  for (int S = 0; S < (1 << numT); ++S)
    for (int x = 0; x < n; ++x)
      OPT[S][x] = INF;

  for (int p = 0; p < numT; ++p) // trivial case
    for (int q = 0; q < n; ++q)
      OPT[1 << p][q] = mat[V[p]][q];

  for (int S = 1; S < (1 << numT); ++S) { // DP step
    if (!(S & (S-1))) continue;
    for (int p = 0; p < n; ++p)
      for (int E = 0; E < S; ++E)
        if ((E | S) == S)
          OPT[S][p] = min( OPT[S][p], OPT[E][p] + OPT[S-E][p] );
    for (int p = 0; p < n; ++p)
      for (int q = 0; q < n; ++q)
        OPT[S][p] = min( OPT[S][p], OPT[S][q] + mat[p][q] );
  }
  int ans = INF;
  for (int S = 0; S < (1 << numT); ++S)
    for (int q = 0; q < n; ++q)
      ans = min(ans, OPT[S][q] + OPT[((1 << numT)-1)-S][q]);
  return ans;
}

int main(){
  int i, j, k, mask;
  int res = INF, tmp, r;
  int ind[100];
  void *mem = malloc(10000000);

  reader(&N,&M,&T);
  rep(i,M) reader(A+i,B+i,C+i), A[i]--, B[i]--;
  rep(i,T) reader(V+i), V[i]--;

  rep(i,N) rep(j,N) mat[i][j] = INF;
  rep(i,N) mat[i][i] = 0;
  rep(i,M) mat[A[i]][B[i]] = mat[B[i]][A[i]] = C[i];
  rep(k,N) rep(i,N) rep(j,N) mat[i][j] = min(mat[i][j], mat[i][k]+mat[k][j]);

  if(T <= 13){
    res = prefield();
  } else {
    rep(i,N) use[i] = 1;
    rep(i,T) use[V[i]] = 0;
    T = 0;
    rep(i,N) if(use[i]) V[T++] = i;
    sort(M,C,A,B,mem);
    rep(mask, 1<<T){
      tmp = 0;
      r = N-T-1;
      rep(i,T) if(mask&1<<i) use[V[i]] = 0, r++;
      unionInit(ind, N);
      rep(i,M) if(!use[A[i]] && !use[B[i]]){
        if(unionConnect(ind, A[i], B[i])) tmp += C[i], r--;
        if(tmp >= res || r==0) break;
      }
      rep(i,T) if(mask&1<<i) use[V[i]] = 1;
      if(r) continue;
      res = min(res, tmp);
    }
  }

  writerLn(res);

  return 0;
}