import numpy as np

def test(input, solution):
    # print(f"Running input {input}")
    result = process(input)
    print(f"Solution was {result}")
    assert result == solution

def run():
    file = open("input.txt", "r")
    return process(file.read()[:-1])

def process_line(line):
    (direction, amount, _) = line.split()
    return direction, int(amount)

direction_map = {"L": (0,-1), "R": (0,1), "D": (-1,0), "U": (1,0)}

def process(input):
    points = []
    perimeter_area = 0
    current_point = (0,0)
    for line in input.split("\n"):
        (dir_letter, amount) = process_line(line)
        direction = (direction_map[dir_letter][0] * amount, direction_map[dir_letter][1] * amount)
        perimeter_area += amount
        current_point = (current_point[0] + direction[0], current_point[1] + direction[1])
        points.append(current_point)
    indices = list(range(len(points) - 1)) + [-1]
    determinants = [np.linalg.det(np.array([[points[i][1], points[i+1][1]],[points[i][0], points[i+1][0]]])) for i in indices]
    return round(abs(sum(determinants))/2) + perimeter_area/2 + 1