n,m = map(int,input().split())
h = list(map(int,input().split()))
graph = [[] for i in range(n+1)]
for i in range(m):
  a,b = map(int,input().split())
  graph[a-1].append(b-1)
  graph[b-1].append(a-1)

for i in range(n):
  graph[i].sort()

INF = 10**18
dp = [[-INF,-INF] for i in range(n)]
dp[0] = [0,0]
for crr in range(n):
  hc = h[crr]
  for nxt in graph[crr][::-1]:
    if crr > nxt: break
    hn = h[nxt]
    if hn > hc:
      dp[nxt][1] = max(dp[nxt][1], dp[crr][0] + hn - hc)
    else:
      dp[nxt][0] = max(dp[nxt][0], dp[crr][1], dp[crr][0])
ans = max(dp[-1])
print(-1) if ans < 0 else print(ans)

dp = [[-INF,-INF] for i in range(n)]
dp[n-1] = [0,0]
for crr in range(n)[::-1]:
  hc = h[crr]
  for nxt in graph[crr]:
    if crr < nxt: break
    hn = h[nxt]
    if hn > hc:
      dp[nxt][1] = max(dp[nxt][1], dp[crr][0] + hn - hc)
    else:
      dp[nxt][0] = max(dp[nxt][0], dp[crr][1], dp[crr][0])

ans = max(dp[0])
print(-1) if ans < 0 else print(ans)