import itertools as iter
import collections as coll
import heapq as hq
import bisect as bis
from decimal import Decimal as dec
from functools import cmp_to_key
import math
import sys
#import pypyjit
#pypyjit.set_param('max_unroll_recursion=-1')
sys.setrecursionlimit(10 ** 6)
inp = sys.stdin.readline
input = lambda : inp().rstrip()
getN = lambda : int(inp())
getNs = lambda : map(int, inp().split())
getList = lambda :list(map(int, inp().split()))
getStrs = lambda n : [input() for _ in [0] * n]
def yexit(): print("Yes"); exit(0)
def nexit(): print("No"); exit(0)
pi = 3.141592653589793
mod = 1000000007
MOD = 998244353
INF = 4611686018427387903
dx = [1, 0, -1, 0];	dy = [0, 1, 0, -1]


"""
Main Code
"""

n, m = getNs()
pst = set([])
qst = set([])
for x, y in [getList() for _ in [0] * m]:
	pst.add(x + y - 2)
	qst.add(x - y)

ans = 0
que = [coll.deque([]) for _ in [0] * 2]
for p in sorted(pst):
	ans += min(p, n - 1) - max(0, -n + p + 1) + 1
	que[p & 1].append(p)
for q in qst:
	ans += min(n + q - 1, n - 1) - max(0, q) + 1

for q in sorted([abs(q) for q in qst]):
	b = q & 1
	while(len(que[b]) > 0 and que[b][0] < q):
		que[b].popleft()
	while(len(que[b]) > 0 and que[b][-1] > 2 * (n - 1) - q):
		que[b].pop()
	ans -= len(que[b])
print(ans)