N = int(input())
A = list(map(int, input().split()))

nim = 0
for a in A:
    nim ^= a
t = 1 if nim else 0
print(t, flush=True)
if t == 0:
    idx, k = map(int, input().split())
    idx -= 1
    nim = A[idx]
    A[idx] -= k
    nim ^= A[idx]

    ret = int(input())
    if ret == -1:
        exit()

while True:
    for i, a in enumerate(A):
        na = a ^ nim
        if na < a:
            A[i] -= a - na
            print(i + 1, a - na, flush=True)
            break

    ret = int(input())
    if ret == -1:
        exit()

    idx, k = map(int, input().split())
    idx -= 1
    nim = A[idx]
    A[idx] -= k
    nim ^= A[idx]

    ret = int(input())
    if ret == -1:
        exit()