import sys
input = sys.stdin.readline

from collections import deque

N,X0,Y0=map(int,input().split())

X=[]
Y=[]

for i in range(N):
    x,y=map(int,input().split())
    X.append(x-1)
    Y.append(y-1)

X.sort()

LIST=[]
for x in X:
    LIST.append((x+X0//2)%X0)
    LIST.append((x+X0//2+1)%X0)

LIST=sorted(set(LIST))

ANS=0
now=0

LEFT=[]
RIGHT=[]

xx=LIST[0]

for x in X:
    left=(xx-x)%X0
    right=(x-xx)%X0

    if left<=right:
        now+=left
        LEFT.append(x)
    else:
        now+=right
        RIGHT.append(x)

LEFT.sort(key=lambda x:(xx-x)%X0,reverse=True)
RIGHT.sort(key=lambda x:(x-xx)%X0)

LEFT=deque(LEFT)
RIGHT=deque(RIGHT)

ANS=now

#print(now,LEFT,RIGHT)

for i in range(1,len(LIST)):
    mae=LIST[i-1]
    xx=LIST[i]

    now+=len(LEFT)*(LIST[i]-LIST[i-1])-len(RIGHT)*(LIST[i]-LIST[i-1])

    #print(now)

    while RIGHT:
        x=RIGHT[0]
        if (x-mae)%X0<(xx-mae):
            RIGHT.popleft()
            now-=(x-mae)%X0-(xx-mae)
            LEFT.append(x)
            now+=(xx-x)%X0
        else:
            break

    while LEFT:
        x=LEFT[0]
        left=(xx-x)%X0
        right=(x-xx)%X0

        #print("!",left,right)

        if right<=left:
            LEFT.popleft()
            RIGHT.append(x)
            now+=right-left
        else:
            break



    #print(now,LEFT,RIGHT)

    while RIGHT:
        x=RIGHT[0]
        left=(xx-x)%X0
        right=(x-xx)%X0

        if left<right:
            RIGHT.popleft()
            LEFT.append(x)
            now+=left-right
        else:
            break

    #print(xx,now,LEFT,RIGHT)

    ANS=max(ANS,now)



X=Y
X0=Y0
X.sort()

LIST=[]
for x in X:
    LIST.append((x+X0//2)%X0)
    LIST.append((x+X0//2+1)%X0)

LIST=sorted(set(LIST))

ANS2=0
now=0

LEFT=[]
RIGHT=[]

xx=LIST[0]

for x in X:
    left=(xx-x)%X0
    right=(x-xx)%X0

    if left<=right:
        now+=left
        LEFT.append(x)
    else:
        now+=right
        RIGHT.append(x)

LEFT.sort(key=lambda x:(xx-x)%X0,reverse=True)
RIGHT.sort(key=lambda x:(x-xx)%X0)

LEFT=deque(LEFT)
RIGHT=deque(RIGHT)

ANS2=now

#print(now,LEFT,RIGHT)

for i in range(1,len(LIST)):
    mae=LIST[i-1]
    xx=LIST[i]

    now+=len(LEFT)*(LIST[i]-LIST[i-1])-len(RIGHT)*(LIST[i]-LIST[i-1])

    #print(now)

    while RIGHT:
        x=RIGHT[0]
        if (x-mae)%X0<(xx-mae):
            RIGHT.popleft()
            now-=(x-mae)%X0-(xx-mae)
            LEFT.append(x)
            now+=(xx-x)%X0
        else:
            break

    while LEFT:
        x=LEFT[0]
        left=(xx-x)%X0
        right=(x-xx)%X0

        #print("!",left,right)

        if right<=left:
            LEFT.popleft()
            RIGHT.append(x)
            now+=right-left
        else:
            break



    #print(now,LEFT,RIGHT)

    while RIGHT:
        x=RIGHT[0]
        left=(xx-x)%X0
        right=(x-xx)%X0

        if left<right:
            RIGHT.popleft()
            LEFT.append(x)
            now+=left-right
        else:
            break

    #print(xx,now,LEFT,RIGHT)

    ANS2=max(ANS2,now)

print(ANS+ANS2)