#!/usr/bin/env python3
import re

def main():
    board_size = 1000
    content = open('input', 'r').readlines()
    content = list(map(str.strip, content))
    board = [[0 for _ in range(board_size)] for _ in range(board_size)]
    for line in content:
        m = re.match('^(\d+),(\d+) -> (\d+),(\d+)', line)
        x1, y1, x2, y2 = tuple(map(int, m.groups(1)))
        if x1 == x2: # move in y
            if y2 < y1:
                y1, y2 = y2, y1
            assert(y1 < y2)
            print(f'marking from {x1},{y1} to {x2},{y2}')
            for y in range(y1, y2+1):
                board[y][x1] += 1
        elif y1 == y2: # move in x
            if x2 < x1:
                x1, x2 = x2, x1
            print(f'marking from {x1},{y1} to {x2},{y2}')
            assert(x1 < x2)
            for x in range(x1, x2+1):
                board[y1][x] += 1 
        else: # move diagonal
            # 
            offset_x = x2 - x1
            offset_y = y2 - y1
            if offset_x > 0: x_step = 1
            else: x_step = -1

            if offset_y > 0: y_step = 1
            else: y_step = -1

            for offset in range(abs(x2-x1)+1):
                board[y1+(offset*y_step)][x1+(offset*x_step)] += 1
            print(f'diagonal: going from {x1},{y1} to {x2},{y2} -> ')

    hotspots = 0
    for line in board:
        for cell in line:
            if cell > 1:
                hotspots += 1
    print(hotspots)



if __name__ == "__main__":
    main()