def tofixed(numObj, digits=0):
    return f"{numObj:.{digits}f}"


n = int(input())
ma = -8800555252512343
mi = 22813372281337322
ma2 = -8800555252512343
mi2 = 22813372281337322
mab = -880055525251234
mab2 = -880055525251234
k1 = 0
k2 = 0
for i in range(n):
    a, b = map(int, input().split())
    if a == 0:
        continue
    if b == 0:
        if a < 0:
            k1 += 1
            if a > ma:
                ma = a
            if a < mi:
                mi = a
        else:
            k2 += 1
            if a > ma2:
                ma2 = a
            if a < mi2:
                mi2 = a
    else:
        if a < 0:
            if abs(b) > mab:
                mab = abs(b)
        else:
            if abs(b) > mab2:
                mab2 = abs(b)
if (mab == -880055525251234 and mab2 == -880055525251234)  or (k1 < 2 and k2 < 2):
    print(tofixed(0.0, 1))
else:
    print(tofixed(max((abs(mi - ma) * mab / 2), abs(mi2 - ma2) * mab2 / 2), 1))
#print(abs(mi - ma), mab)