2563

import sys

sys.stdin = open("input.txt","rt")

arr = [[0 for _ in range(101)] for _ in range(101)]

n = int(input())

for _ in range(n):

    x,y = map(int, input().split())

    for row in range(x, x+10):
        for col in range(y, y+10):
            arr[row][col] = 1


result = 0

for i in arr:
    result += i.count(1)

print(result)

---------------------

import sys
sys.stdin = open("input.txt","rt")

ary = [[0 for _ in range(101)] for _ in range(101)]

n = int(input())

for k in range(n):

    row, col = map(int, input().split())

    for x in range(10):
        for y in range(10):
            ary[row + x][col + y] = 1


sum_val = 0

for x in ary:

    sum_val += x.count(1)

print(sum_val)