import fractions
import sys, time, random
from collections import deque, Counter, defaultdict
input = lambda: sys.stdin.readline().rstrip()
ii = lambda: int(input())
mi = lambda: map(int, input().split())
li = lambda: list(mi())
inf = 2 ** 63 - 1
mod = 998244353
from heapq import heappush, heappop
class MinCostFlow:
    INF = 10**18
 
    def __init__(self, N):
        self.N = N
        self.G = [[] for i in range(N)]
 
    def add_edge(self, fr, to, cap, cost):
        forward = [to, cap, cost, None]
        backward = forward[3] = [fr, 0, -cost, forward]
        self.G[fr].append(forward)
        self.G[to].append(backward)
 
    def flow(self, s, t, f):
        N = self.N; G = self.G
        INF = MinCostFlow.INF
 
        res = 0
        H = [0]*N
        prv_v = [0]*N
        prv_e = [None]*N
 
        d0 = [INF]*N
        dist = [INF]*N
 
        while f:
            dist[:] = d0
            dist[s] = 0
            que = [(0, s)]
 
            while que:
                c, v = heappop(que)
                if dist[v] < c:
                    continue
                r0 = dist[v] + H[v]
                for e in G[v]:
                    w, cap, cost, _ = e
                    if cap > 0 and r0 + cost - H[w] < dist[w]:
                        dist[w] = r = r0 + cost - H[w]
                        prv_v[w] = v; prv_e[w] = e
                        heappush(que, (r, w))
            if dist[t] == INF:
                return None
 
            for i in range(N):
                H[i] += dist[i]
 
            d = f; v = t
            while v != s:
                d = min(d, prv_e[v][1])
                v = prv_v[v]
            f -= d
            res += d * H[t]
            v = t
            while v != s:
                e = prv_e[v]
                e[1] -= d
                e[3][1] += d
                v = prv_v[v]
        return res
k, n, m = mi()

a = li()
C = Counter(a)
b = li()

G = MinCostFlow(n + 2)
S = n
T = n + 1

for i in range(n):
    G.add_edge(S, i, C[i + 1], 0)
    G.add_edge(i, T, b[i], 0)
for _ in range(m):
    u, v, d = mi()
    u -= 1; v -= 1
    G.add_edge(u, v, inf, d)
    G.add_edge(v, u, inf, d)
    
f = G.flow(S, T, k)

print(f)