N, M = map(int, input().split())
H = list(map(int, input().split()))
XY = [list(map(int, input().split())) for _ in range(M)]
# dp[i][j]:= 足場iにいてその前の移動が昇り:1,下り:0のときの登った回数の最大値
E = [[] for _ in range(N)]
for x, y in XY:
    E[x - 1].append(y - 1)
dp = [[-10 ** 12, -10 ** 12] for _ in range(N)]
for x in range(N - 1):
    for y in E[x]:
        hx = H[x]
        hy = H[y]
        if x == 0:
            if hx < hy:
                dp[y][1] = max(dp[y][1], max(dp[x][0], dp[x][1], 0) + hy - hx)
            else:
                dp[y][0] = max(dp[y][0], dp[x][0], dp[x][1], 0)
        else:
            if hx < hy:
                dp[y][1] = max(dp[y][1], dp[x][0] + hy - hx)
            else:
                dp[y][0] = max(dp[y][0], dp[x][1])
ans = []
ans.append(max(dp[N - 1]))
E = [[] for _ in range(N)]
for x, y in XY:
    E[y - 1].append(x - 1)
dp = [-10 ** 12] * N
for y in reversed(range(1, N)):
    for x in E[y]:
        hx = H[x]
        hy = H[y]
        if y == N - 1:
            if hx > hy:
                dp[x] = max(dp[x], max(dp[y], 0) + hx - hy)
            else:
                dp[x] = max(dp[x], dp[y], 0)
        else:
            if hx > hy:
                dp[x] = max(dp[x], dp[y] + hx - hy)
            else:
                dp[x] = max(dp[x], dp[y])
ans.append(dp[0])
for i in range(2):
    if ans[i] < 0:
        print(-1)
    else:
        print(ans[i])