ZFTSH Programming Elements Task 9

a, b, c, d = map(int, input().split())

one = -(a + b + c + d)
two = a*b + a*c + a*d + b*c + b*d + c*d
three = -(a*b*c + a*b*d + a*c*d + b*c*d)
four = a*b*c*d

def f(x):
    if x > 0:
        if x == 1:
            res = ' + '
        else:
            res = f' + {x}'
    elif x < 0:
        if x == -1:
            res = ' - '
        else:
            res = f' - {abs(x)}'
    else:
        res = ''
    return res

x3 = x2 = x = zero = ''
if f(one) != '':
    x3 = f'{f(one)}x^3'
if f(two) != '':
    x2 = f'{f(two)}x^2'
if f(three) != '':
    x = f'{f(three)}x'
if f(four) != '':
    zero = f'{f(four)}'
    if zero == ' + ':
        zero = ' + 1'
    elif zero == ' - ':
        zero = ' - 1'

print('x^4', x3, x2, x, zero, sep='')