#!/usr/bin/env python

import re
from collections import defaultdict

RE_INPUT = re.compile(r'^(\d+),(\d+)\s*\->\s*(\d+),(\d+)')

def read_file(filename):
    file = open(filename, 'r')
    while True:
        line = file.readline()
        if not line:
            break
        yield line

def process_vent(coord, see_map):
    if coord[0] == coord[2]:
        c_max = max(coord[1], coord[3])+1
        c_min = min(coord[1], coord[3])

        for i in range(c_min, c_max):
            k = "%d,%d" % (coord[0], i)
            see_map[k] += 1
    if coord[1] == coord[3]:
        c_max = max(coord[0], coord[2])+1
        c_min = min(coord[0], coord[2])

        for i in range(c_min, c_max):
            k = "%d,%d" % (i, coord[1])
            see_map[k] += 1

def main():
    see_map = defaultdict(int)
    for line in read_file('input01.txt'):
        match = re.search(RE_INPUT, line)
        if not match:
            print("wrong syntax")
        vent =  [int(i) for i in match.groups()]
        if (not (vent[0] == vent[2] or vent[1] == vent[3])):
            continue
        process_vent(vent, see_map)
    
    result = sum([1 for i in see_map.values() if i > 1])
    print(result)

if __name__ == "__main__":
    main()