import sys
from PyQt5.QtWidgets import QApplication, QWidget, QPushButton, QLabel
from PyQt5.QtWidgets import QLCDNumber, QLineEdit


class Example(QWidget):
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        self.setGeometry(300, 300, 300, 300)
        self.setWindowTitle('Миникалькулятор')

        self.btn = QPushButton('Рассчитать', self)
        self.btn.resize(self.btn.sizeHint())
        self.btn.move(100, 150)
        self.btn.clicked.connect(self.func)

        self.LCD_count = QLCDNumber(self)
        self.LCD_count.move(10, 10)

        self.LCD_count2 = QLCDNumber(self)
        self.LCD_count2.move(10, 40)

        self.LCD_count3 = QLCDNumber(self)
        self.LCD_count3.move(10, 70)

        self.LCD_count4 = QLCDNumber(self)
        self.LCD_count4.move(10, 100)

        self.first = QLineEdit(self)
        self.first.move(90, 10)
        self.first.resize(50, 20)

        self.second = QLineEdit(self)
        self.second.move(90, 40)
        self.second.resize(50, 20)

    def func(self):
        number_1 = self.first.text()
        number_2 = self.second.text()
        self.LCD_count.display(int(number_1) + int(number_2))
        self.LCD_count2.display(int(number_1) - int(number_2))
        self.LCD_count3.display(int(number_1) / int(number_2))
        self.LCD_count4.display(int(number_1) * int(number_2))


if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = Example()
    ex.show()
    sys.exit(app.exec())