local function uf_initialize(n)
  local parent = {}
  for i = 1, n do parent[i] = i end
  return parent
end

local function uf_findroot(idx, parent)
  while parent[idx] ~= idx do
    idx = parent[idx]
  end
  return idx
end

local function kruskal(parent, line, force)
  -- line.c, line.i1, line.i2
  table.sort(line, function(a, b) return a.c < b.c end)
  local totalcost = 0
  local linenum = #line
  for i = 1, linenum do
    local c, i1, i2 = line[i].c, line[i].i1, line[i].i2
    local r1, r2 = uf_findroot(i1, parent), uf_findroot(i2, parent)
    parent[i1], parent[i2] = r1, r2
    if force or r1 ~= r2 then
      parent[r2] = r1
      parent[i2] = r1
      totalcost = totalcost + c
    end
  end
  return totalcost
end

local n, m, k = io.read("*n", "*n", "*n")
local a, b, c = {}, {}, {}
local allcost = 0
for i = 1, m do
  a[i], b[i], c[i] = io.read("*n", "*n", "*n")
  allcost = allcost + c[i]
end
local curpos = 1
local forceline, line = {}, {}
for i = 1, k do
  local e = io.read("*n")
  local tmp = {}
  for j = curpos, e - 1 do
    tmp.i1, tmp.i2, tmp.c = a[j], b[j], c[j]
    table.insert(line, tmp)
  end
  tmp.i1, tmp.i2, tmp.c = a[e], b[e], c[e]
  table.insert(forceline, tmp)
  curpos = e + 1
end
for i = curpos, n do
  local tmp = {}
  tmp.i1, tmp.i2, tmp.c = a[i], b[i], c[i]
  table.insert(line, tmp)
end

local parent = uf_initialize(n)
local cost = kruskal(parent, forceline, true)
cost = cost + kruskal(parent, line, false)
print(allcost - cost)