import typing
import math
import sys
import copy
import itertools
import collections
import bisect
import heapq
import decimal
import random
import gc
# region template
def ni(): return int(sys.stdin.readline())
def ns(): return map(int, sys.stdin.readline().split())
def ns1(): return map(lambda x: int(x)-1, sys.stdin.readline().split())
def na(): return list(map(int, sys.stdin.readline().split()))
def na1(): return list(map(lambda x: int(x)-1, sys.stdin.readline().split()))
def nall(): return list(map(int, sys.stdin.read().split()))
def flush(): return sys.stdout.flush()
def nib(): return int(sys.stdin.buffer.readline())
def nsb(): return map(int, sys.stdin.buffer.readline().split())
def ns1b(): return map(lambda x: int(x)-1, sys.stdin.buffer.readline().split())
def nab(): return list(map(int, sys.stdin.buffer.readline().split()))
def na1b(): return list(map(lambda x: int(x)-1, sys.stdin.buffer.readline().split()))
def nallb(): return list(map(int, sys.stdin.buffer.read().split()))
# endregion


# sys.setrecursionlimit(10**7+1)
inf = 10**20
mod = 10**9+7
# mod = 998244353


def main():
    L, N = ns()
    r = set()  # 右肩下がり
    l = set()  # 左肩下がり
    for _ in range(N):
        x, y = ns()
        l.add(x+y-2)
        r.add(x-y)

    r = list(r)
    l = list(l)
    lodd = []
    leven = []
    for li in l:
        if li % 2:
            lodd.append(li)
        else:
            leven.append(li)

    r.sort()
    lodd.sort()
    leven.sort()

    res = 0
    for x in l:
        res += max(0, L-abs(L-x-1))

    for x in r:
        res += max(0, L-abs(x))
        # いくつlと交差しますか？
        if x < 0:
            s = abs(x)
            t = L-1 + L-1-s
        else:
            s = x
            t = L-1+L-1-s

        if x % 2:
            sidx = bisect.bisect_left(lodd, s-1)
            tidx = bisect.bisect_right(lodd, t)
        else:
            sidx = bisect.bisect_left(leven, s-1)
            tidx = bisect.bisect_right(leven, t)
        res -= tidx-sidx

    print(res)


if __name__ == '__main__':
    main()