#!/usr/bin/env python3

from pprint import pprint

with open('input.txt', 'r') as f:
    coords = [x.strip().split(', ') for x in f.readlines()]
    coords = [tuple(map(lambda y: int(y), x)) for x in coords]

# print(coords)

def distance(p1, p2):
    """Manhattan distance"""
    return abs(p2[0] - p1[0]) + abs(p2[1] - p1[1])

min_x = min([x[0] for x in coords])
max_x = max([x[0] for x in coords])
min_y = min([x[1] for x in coords])
max_y = max([x[1] for x in coords])

res = 0
for x in range(min_x, max_x + 1):
    for y in range(min_y, max_y + 1):
        point = (x, y)
        dist_sum = sum([distance(x, point) for x in coords])
        if dist_sum < 10000:
            res += 1 

print(res)