#!/usr/bin/env python3
import re
from collections import defaultdict
from itertools import repeat

lines = (x.strip() for x in open("input.txt"))
points = defaultdict(int)

for line in lines:
    [x1, y1, x2, y2] = list(map(int, re.match(r"(\d+),(\d+) -> (\d+),(\d+)", line).groups()))
    for x, y in zip(
            range(x1, x2+(x1 <= x2)*2-1, (x1 <= x2)*2-1) if x1 != x2 else repeat(x1),
            range(y1, y2+(y1 <= y2)*2-1, (y1 <= y2)*2-1) if y1 != y2 else repeat(y1)
    ):
        key = '{},{}'.format(x, y)
        points[key] = points[key] + 1

print(sum(val >= 2 for val in points.values()))