class SquareUnit:
    def __init__(self, edge_length: int):
        self.edge_length = edge_length

    def area(self) -> int:
        return self.edge_length ** 2

def main():
    edge = int(input().strip())
    
    if edge <= 0:
        print("Invalid input")
        return
    
    square = SquareUnit(edge)
    print(f"Area of square: {square.area()} square meters")

if __name__ == "__main__":
    main()