var p,ff,c:longint;
    t:array[0..501,0..501]of longint;
    f,s:array[0..501]of longint;

    i,j,k,x,y,z,ans,min:longint;
begin
assign(input,'bestspot.in');reset(input);
assign(output,'bestspot.out');rewrite(output);
readln(p,ff,c);
for i:=1 to ff do readln(f[i]);
for i:=ff+2 to c+ff+1 do
  begin
  readln(x,y,z);
  t[x,y]:=z;t[y,x]:=z;
  end;
for i:=1 to p do
 for j:=1 to p do
  if t[i,j]=0 then t[i,j]:=99999;

for i:=1 to p do
  for k:=1 to p do
  if (t[i,k]>0)and(i<>k) then
    begin
    for j:=1 to p do
    if (t[k,j]>0)and(i<>j)and(k<>j) then
      begin
      if (t[i,k]+t[k,j]<t[i,j]) then
      t[i,j]:=t[i,k]+t[k,j];
      t[j,i]:=t[i,j];
      end;
    end;
min:=maxlongint; ans:=0;
for i:=1 to p do
  begin
  for j:=1 to ff do
     s[i]:=t[i,j]+s[i];
  if s[i]<min then begin min:=s[i];ans:=i; end;
  end;
writeln(ans);
close(input);close(output);
end.