Buggy python submission (verdict: Runtime Error):
import bisect
n = int(input())
a = [int(i) for i in input().split()]
a.sort()
point = bisect.bisect_right(a, 0)
a_minus = a[:point]
a_plus = a[point:]
len_plus = len(a_plus)
if (len(a_minus) > 0) & (len(a_plus) > 0):
    ans = sum(a_plus) - sum(a_minus)
    print(ans)
    for i in range(len(a_plus)):
        if len(a_plus) == 1:
            x = a_plus.pop(0)
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        elif (i == 0):
            x = a_minus.pop(0)
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 1:
            y = x - y
            x = a_plus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
    for j in range(len(a_minus)):
        x = x - y
        y = a_minus.pop(0)
        print(str(x) + ' ' + str(y))
elif len(a_plus) > 0:
    ans = sum(a_plus) - ((a[0]) * 2)
    print(ans)
    for i in range(len(a_plus) - 1):
        if i == 0:
            x = a_plus.pop(0)
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 2:
            y = x - y
            x = a_plus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
elif len(a_minus) > 0:
    ans = (a_minus[-1] * 2) - sum(a_minus)
    print(ans)
    for i in range(len(a_minus) - 1):
        if i == 0:
            x = a_minus[-1]
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 2:
            x = x - y
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))

Fixed submission:
import bisect
n = int(input())
a = [int(i) for i in input().split()]
a.sort()
point = bisect.bisect_right(a, 0)
a_minus = a[:point]
a_plus = a[point:]
len_plus = len(a_plus)
if (len(a_minus) > 0) & (len(a_plus) > 0):
    ans = sum(a_plus) - sum(a_minus)
    print(ans)
    for i in range(len(a_plus)):
        if len_plus == 1:
            x = a_plus.pop(0)
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        elif (i == 0):
            x = a_minus.pop(0)
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 1:
            y = x - y
            x = a_plus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
    for j in range(len(a_minus)):
        x = x - y
        y = a_minus.pop(0)
        print(str(x) + ' ' + str(y))
elif len(a_plus) > 0:
    ans = sum(a_plus) - ((a[0]) * 2)
    print(ans)
    for i in range(len(a_plus) - 1):
        if i == 0:
            x = a_plus.pop(0)
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 2:
            y = x - y
            x = a_plus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
elif len(a_minus) > 0:
    ans = (a_minus[-1] * 2) - sum(a_minus)
    print(ans)
    for i in range(len(a_minus) - 1):
        if i == 0:
            x = a_minus[-1]
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 2:
            x = x - y
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))

Buggy python submission (verdict: Runtime Error):
import bisect
n = int(input())
a = [int(i) for i in input().split()]
a.sort()
point = bisect.bisect_right(a, 0)
a_minus = a[:point]
a_plus = a[point:]
len_plus = len(a_plus)
if len(a_minus) > 0:
    ans = sum(a_plus) - sum(a_minus)
    print(ans)
    for i in range(len(a_plus)):
        if i == 0:
            x = a_minus.pop(0)
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 1:
            y = x - y
            x = a_plus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
    for j in range(len(a_minus)):
        x = x - y
        y = a_minus.pop(0)
        print(str(x) + ' ' + str(y))
else:
    ans = sum(a_plus) - ((a[0]) * 2)
    print(ans)
    for i in range(len(a_plus) - 1):
        if i == 0:
            x = a_plus.pop(0)
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 2:
            y = x - y
            x = a_plus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))

Fixed submission:
import bisect
n = int(input())
a = [int(i) for i in input().split()]
a.sort()
point = bisect.bisect_right(a, 0)
a_minus = a[:point]
a_plus = a[point:]
len_plus = len(a_plus)
if (len(a_minus) > 0) & (len(a_plus) > 0):
    ans = sum(a_plus) - sum(a_minus)
    print(ans)
    for i in range(len(a_plus)):
        if len_plus == 1:
            x = a_plus.pop(0)
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        elif (i == 0):
            x = a_minus.pop(0)
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 1:
            y = x - y
            x = a_plus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
    for j in range(len(a_minus)):
        x = x - y
        y = a_minus.pop(0)
        print(str(x) + ' ' + str(y))
elif len(a_plus) > 0:
    ans = sum(a_plus) - ((a[0]) * 2)
    print(ans)
    for i in range(len(a_plus) - 1):
        if i == 0:
            x = a_plus.pop(0)
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 2:
            y = x - y
            x = a_plus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
elif len(a_minus) > 0:
    ans = (a_minus[-1] * 2) - sum(a_minus)
    print(ans)
    for i in range(len(a_minus) - 1):
        if i == 0:
            x = a_minus[-1]
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 2:
            x = x - y
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))

Buggy python submission (verdict: Runtime Error):
n = int(input())
a = [int(i) for i in input().split()]
a.sort()
if n % 2 == 0:
    k = n // 2
else:
    k = (n // 2) + 1
a_1 = a[0:k-1]
a_2 = a[k-1:]
ans = - sum(a_1) + sum(a_2)
print(ans)
if n % 2 == 1:
    for i in range(n - 1):
        if i == 0:
            x = a_1.pop(0)            
            y = a_2.pop(0)
            print(str(x) + " " + str(y))
        else:
            if i % 2 == 0:
                y = x - y
                x = a_1.pop(0)
                print(str(x) + " " + str(y))
            elif i % 2 == 1:
                y = x - y
                x = a_2.pop(0)
                print(str(x) + " " + str(y))
elif n % 2 == 0:
    for i in range(n - 1):
        if i == 0:
            x = a_2.pop(0)
            y = a_1.pop(0)
            print(str(x) + " " + str(y))
        else:
            if i % 2 == 0:
                y = x - y
                x = a_2.pop(0)
                print(str(x) + " " + str(y))
            elif i % 2 == 1:
                y = x - y
                x = a_1.pop(0)
                print(str(x) + " " + str(y))

Fixed submission:
import bisect
n = int(input())
a = [int(i) for i in input().split()]
a.sort()
point = bisect.bisect_right(a, 0)
a_minus = a[:point]
a_plus = a[point:]
len_plus = len(a_plus)
if (len(a_minus) > 0) & (len(a_plus) > 0):
    ans = sum(a_plus) - sum(a_minus)
    print(ans)
    for i in range(len(a_plus)):
        if len_plus == 1:
            x = a_plus.pop(0)
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        elif (i == 0):
            x = a_minus.pop(0)
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 1:
            y = x - y
            x = a_plus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
    for j in range(len(a_minus)):
        x = x - y
        y = a_minus.pop(0)
        print(str(x) + ' ' + str(y))
elif len(a_plus) > 0:
    ans = sum(a_plus) - ((a[0]) * 2)
    print(ans)
    for i in range(len(a_plus) - 1):
        if i == 0:
            x = a_plus.pop(0)
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 2:
            y = x - y
            x = a_plus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_plus.pop(0)
            print(str(x) + " " + str(y))
elif len(a_minus) > 0:
    ans = (a_minus[-1] * 2) - sum(a_minus)
    print(ans)
    for i in range(len(a_minus) - 1):
        if i == 0:
            x = a_minus[-1]
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        elif i == len_plus - 2:
            x = x - y
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))
        else:
            x = x - y
            y = a_minus.pop(0)
            print(str(x) + " " + str(y))