문제 링크 https://www.acmicpc.net/problem/2563
종이 범위만큼 1로 채워준다.
dohwazi = [[0]*101 for i in range(101)]
n = int(input())
for _ in range(n):
x, y = map(int, input().split())
for i in range(y, y+10):
for j in range(x, x+10):
dohwazi[i][j] = 1
result = 0
for row in dohwazi:
result += row.count(1)
print(result)