n = int(input())
k = int(input())
P = [i for i in range(n)]
for _ in range(k):
    x, y = map(int, input().split())
    x -= 1
    y -= 1
    P[x], P[y] = P[y], P[x]
A = list(map(int, input().split()))
A = [a - 1 for a in A]
invA = [-1] * n
for i, a in enumerate(A):
    invA[a] = i
ans = []
for i, a in enumerate(A):
    while P[i] != a:
        p = invA[P[i]]
        ans.append((i + 1, p + 1))
        P[i], P[p] = P[p], P[i]
print(len(ans))
for row in ans:
    print(*row)