from collections import defaultdict, deque, Counter
from heapq import heappush, heappop, heapify
import math
import bisect
import random
from itertools import permutations, accumulate, combinations, product
import sys
import string
from bisect import bisect_left, bisect_right
from math import factorial, ceil, floor
from functools import reduce


sys.setrecursionlimit(2147483647)
INF = 10 ** 18
def LI(): return list(map(int, sys.stdin.buffer.readline().split()))
def I(): return int(sys.stdin.buffer.readline())
def LS(): return sys.stdin.buffer.readline().rstrip().decode('utf-8').split()
def S(): return sys.stdin.buffer.readline().rstrip().decode('utf-8')
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def LSR(n): return [LS() for i in range(n)]
def SRL(n): return [list(S()) for i in range(n)]
def MSRL(n): return [[int(j) for j in list(S())] for i in range(n)]
mod = 1000000007


n = I()
A = sorted(LI())
if A[0] > 0:
    print(sum(A) - 2 * A[0])
    ret = A[0]
    for i in range(1, n - 1):
        print(ret, A[i])
        ret -= A[i]
    print(A[n - 1], ret)
elif A[-1] < 0:
    print(-sum(A) + A[-1] * 2)
    ret = A[-1]
    for i in range(n - 1):
        print(ret, A[i])
        ret -= A[i]
else:
    print(sum([abs(a) for a in A]))
    minus = [a for a in A if a < 0]
    zero = [a for a in A if a == 0]
    plus = [a for a in A if a > 0]
    if not minus:
        minus += zero
    else:
        plus += zero
    ret = minus[0]
    for j in range(1, len(plus)):
        print(ret, plus[j])
        ret -= plus[j]
    print(plus[0], ret)
    ret = plus[0] - ret
    for k in range(1, len(minus)):
        print(ret, minus[k])
        ret -= minus[k]




### FIXED CODE ###

from collections import defaultdict, deque, Counter
from heapq import heappush, heappop, heapify
from bisect import bisect_right, bisect_left
import random
from itertools import permutations, accumulate, combinations, product
import sys
import string
from bisect import bisect_left, bisect_right
from math import factorial, ceil, floor, gamma, log
from operator import mul
from functools import reduce
from copy import deepcopy

sys.setrecursionlimit(2147483647)
INF = 10 ** 20
def LI(): return list(map(int, sys.stdin.buffer.readline().split()))
def I(): return int(sys.stdin.buffer.readline())
def LS(): return sys.stdin.buffer.readline().rstrip().decode('utf-8').split()
def S(): return sys.stdin.buffer.readline().rstrip().decode('utf-8')
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def LSR(n): return [LS() for i in range(n)]
def SRL(n): return [list(S()) for i in range(n)]
def MSRL(n): return [[int(j) for j in list(S())] for i in range(n)]
mod = 10 ** 9 + 7


n = I()
A = LI()
A.sort()
if all([a > 0 for a in A]):
    now = min(A)
    print(sum(A) - now * 2)
    A.remove(now)
    last = A.pop()
    while A:
        nxt = A.pop()
        print(now, nxt)
        now -= nxt
    print(last, now)
elif all([a < 0 for a in A]):
    now = max(A)
    print(-sum(A) + now * 2)
    A.remove(now)
    while A:
        nxt = A.pop()
        print(now, nxt)
        now -= nxt
else:
    print(sum([abs(i) for i in A]))
    minus = []
    plus = []
    for a in A:
        if a > 0:
            plus += [a]
        elif a < 0:
            minus += [a]
        else:
            if not plus:
                plus += [a]
            else:
                minus += [a]
    ret = minus[0]
    for j in range(1, len(plus)):
        print(ret, plus[j])
        ret -= plus[j]
    print(plus[0], ret)
    ret = plus[0] - ret
    for k in range(1, len(minus)):
        print(ret, minus[k])
        ret -= minus[k]