Hello Everyone,

Basicly, what I need for the program to do is to act a as simple fraction calculator (for addition, subtraction, multiplication and division) for the a single line of input, for example:
-input: 1/7 + 3/5
-output: 26/35

My initial code:

import sys

def euclid(numA, numB):
    while numB != 0:
        numRem = numA % numB
        numA = numB
        numB = numRem
    return numA

for wejscie in sys.stdin:
    wyjscie = wejscie.split(' ')
    a, b = [int(x) for x in wyjscie[0].split("/")]
    c, d = [int(x) for x in wyjscie[2].split("/")]
    if wyjscie[1] == '+':
        licz = a * d + b * c
        mian= b * d
        nwd = euclid(licz, mian)
        konA = licz/nwd
        konB = mian/nwd
        wynik = str(konA) + '/' + str(konB)
        print(wynik)
    elif wyjscie[1] == '-':
        licz= a * d - b * c
        mian= b * d
        nwd = euclid(licz, mian)
        konA = licz/nwd
        konB = mian/nwd
        wynik = str(konA) + '/' + str(konB)
        print(wynik)
    elif wyjscie[1] == '*':
        licz= a * c
        mian= b * d
        nwd = euclid(licz, mian)
        konA = licz/nwd
        konB = mian/nwd
        wynik = str(konA) + '/' + str(konB)
        print(wynik)
    else:
        licz= a * d
        mian= b * c
        nwd = euclid(licz, mian)
        konA = licz/nwd
        konB = mian/nwd
        wynik = str(konA) + '/' + str(konB)
        print(wynik)

Which I reduced to:

import sys

def euclid(numA, numB):
    while numB != 0:
        numRem = numA % numB
        numA = numB
        numB = numRem
    return numA

for wejscie in sys.stdin:
    wyjscie = wejscie.split(' ')
    a, b = [int(x) for x in wyjscie[0].split("/")]
    c, d = [int(x) for x in wyjscie[2].split("/")]
    if wyjscie[1] == '+':
        print("/".join([str((a * d + b * c)/euclid(a * d + b * c, b * d)),str((b * d)/euclid(a * d + b * c, b * d))]))
    elif wyjscie[1] == '-':
        print("/".join([str((a * d - b * c)/euclid(a * d - b * c, b * d)),str((b * d)/euclid(a * d - b * c, b * d))]))
    elif wyjscie[1] == '*':
        print("/".join([str((a * c)/euclid(a * c, b * d)),str((b * d)/euclid(a * c, b * d))]))
    else:
        print("/".join([str((a * d)/euclid(a * d, b * c)),str((b * c)/euclid(a * d, b * c))]))

Any advice on how to improve this futher is welcome.

Edit: one more thing that I forgot to mention - the code can not make use of any libraries apart from sys.