# -*- coding: utf-8 -*-
from tkinter import *

root = Tk()
root.geometry("205x340")
solution = None
screen = Label(root, text = "0", font = "EngraversMT 12")
screen.pack()
def print_zero(event):
    if screen["text"] != "0":
        screen["text"] += "0"
def print_one(event):
    if screen["text"] == "0":
        screen["text"] = "1"
    else:
        screen["text"] += "1"
def print_two(event):
    if screen["text"] == "0":
        screen["text"] = "2"
    else:
        screen["text"] += "2"
def print_three(event):
    if screen["text"] == "0":
        screen["text"] = "3"
    else:
        screen["text"] += "3"
def print_four(event):
    if screen["text"] == "0":
        screen["text"] = "4"
    else:
        screen["text"] += "4"
def print_five(event):
    if screen["text"] == "0":
        screen["text"] = "5"
    else:
        screen["text"] += "5"
def print_six(event):
    if screen["text"] == "0":
        screen["text"] = "6"
    else:
        screen["text"] += "6"
def print_seven(event):
    if screen["text"] == "0":
        screen["text"] = "7"
    else:
        screen["text"] += "7"
def print_eight(event):
    if screen["text"] == "0":
        screen["text"] = "8"
    else:
        screen["text"] += "8"
def print_nine(event):
    if screen["text"] == "0":
        screen["text"] = "9"
    else:
        screen["text"] += "9"
def _enter(event):
    solve = screen["text"].split( )
    if len(solve) == 1:
        pass
    elif solve[1] == "/":
        screen["text"] = str(int(solve[0]) // int(solve[2]))
    elif solve[1] == "*":
        screen["text"] = str(int(solve[0]) * int(solve[2]))
    elif solve[1] == "-":
        screen["text"] = str(int(solve[0]) - int(solve[2]))
    elif solve[1] == "+":
        screen["text"] = str(int(solve[0]) + int(solve[2]))
def division(event):
    _enter(event)
    screen["text"] += " / "
def multiply(event):
    _enter(event)
    screen["text"] += " * "
def _minus(event):
    _enter(event)
    screen["text"] += " - "
def _plus(event):
    _enter(event)
    screen["text"] += " + "
def _backspace(event):
    if len(screen["text"]) > 1:
        screen["text"] = screen["text"][:-1:1]
    else:
        screen["text"] = "0"
def _sqr(event):
    screen["text"] = str(int(screen["text"]) ** 2)
def _clear(event):
    screen["text"] = "0"

div = Button(root, text = "/", width = 5, height = 3)
mul = Button(root, text = "*", width = 5, height = 3)
backspace = Button(root, text = "<--", width = 5, height = 3)
minus = Button(root, text = "-", width = 5, height = 3)
plus = Button(root, text = "+", width = 5, height = 7)
enter = Button(root, text = "=", width = 5, height = 3)
seven = Button(root, text = "7", width = 5, height = 3)
eight = Button(root, text = "8", width = 5, height = 3)
nine = Button(root, text = "9", width = 5, height = 3)
four = Button(root, text = "4", width = 5, height = 3)
five = Button(root, text = "5", width = 5, height = 3)
six = Button(root, text = "6", width = 5, height = 3)
one = Button(root, text = "1", width = 5, height = 3)
two = Button(root, text = "2", width = 5, height = 3)
three = Button(root, text = "3", width = 5, height = 3)
zero = Button(root, text = "0", width = 12, height = 3)
sqr = Button(root, text = "x^2", width = 5, height = 3)
clear = Button(root, text = "C", width = 5, height = 3)
zero.bind("<Button-1>", print_zero)
zero.place(x = 5, y = 280)
one.bind("<Button-1>", print_one)
one.place(x = 5, y = 220)
two.bind("<Button-1>", print_two)
two.place(x = 55, y = 220)
three.bind("<Button-1>", print_three)
three.place(x = 105, y = 220)
four.bind("<Button-1>", print_four)
four.place(x = 5, y = 160)
five.bind("<Button-1>", print_five)
five.place(x = 55, y = 160)
six.bind("<Button-1>", print_six)
six.place(x = 105, y = 160)
seven.bind("<Button-1>", print_seven)
seven.place(x = 5, y = 100)
eight.bind("<Button-1>", print_eight)
eight.place(x = 55, y = 100)
nine.bind("<Button-1>", print_nine)
nine.place(x = 105, y = 100)
sqr.bind("<Button-1>", _sqr)
sqr.place(x = 105, y = 40)
clear.bind("<Button-1>", _clear)
clear.place(x = 105, y = 280)
backspace.bind("<Button-1>", _backspace)
backspace.place(x = 155, y = 40)
div.bind("<Button-1>", division)
div.place(x = 5, y = 40)
mul.bind("<Button-1>", multiply)
mul.place(x = 55, y = 40)
minus.bind("<Button-1>", _minus)
minus.place(x = 155, y = 100)
plus.bind("<Button-1>", _plus)
plus.place(x = 155, y = 160)
enter.bind("<Button-1>", _enter)
enter.place(x = 155, y = 280)
root.mainloop()