Buggy python submission (verdict: Time Limit Exceeded):
import sys
from bisect import bisect_right,bisect_left
def I(): return int(sys.stdin.readline().rstrip())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))  #空白あり


N = I()
A,B = LI(),LI()

# 各桁の xor を考える

ans = 0
mod = 1 << 29
for i in range(29,0,-1):  # 2**(i-1) の位
    X = [A[j] & (mod-1) for j in range(N)]
    Y = [B[j] & (mod-1) for j in range(N)]
    Y.sort()
    mod >>= 1
    r = 0
    for j in range(N):
        a = X[j]
        # [2**(i-1)-a,2*2**(i-1)-a),[3*2**(i-1)-a,4*2**(i-1)-a) にある Y の要素の個数を数え上げる
        r += bisect_right(Y,2*mod-a-1) - bisect_left(Y,mod-a)
        r += bisect_right(Y,4*mod-a-1) - bisect_left(Y,3*mod-a)
    if r % 2 == 1:
        ans += mod

print(ans)


Fixed submission:
import sys
from bisect import bisect_right,bisect_left
def I(): return int(sys.stdin.readline().rstrip())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))  #空白あり


N = I()
A,B = LI(),LI()

# 各桁の xor を考える

ans = 0
mod = 1 << 29
for i in range(29,0,-1):  # 2**(i-1) の位
    X = [a & (mod-1) for a in A]
    Y = [b & (mod-1) for b in B]
    X.sort()
    Y.sort(reverse=True)
    mod >>= 1
    r = 0
    i1,i2,i3 = 0,0,0
    for j in range(N):
        x = X[j]
        # [2**(i-1)-x,2*2**(i-1)-x),[3*2**(i-1)-x,4*2**(i-1)-x) にある Y の要素の個数を数え上げる
        # 尺取り法
        while i1 < N and Y[i1] >= mod-x:
            i1 += 1
        while i2 < N and Y[i2] >= 2*mod-x:
            i2 += 1
        while i3 < N and Y[i3] >= 3*mod-x:
            i3 += 1
        r += i1-i2+i3
    if r % 2 == 1:
        ans += mod

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from bisect import bisect_right,bisect_left
def I(): return int(sys.stdin.readline().rstrip())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))  #空白あり


N = I()
A,B = LI(),LI()

# 各桁の xor を考える

ans = 0
mod = 2**29
for i in range(29,0,-1):  # 2**(i-1) の位
    X = [A[j] % mod for j in range(N)]
    Y = [B[j] % mod for j in range(N)]
    Y.sort()
    mod >>= 1
    r = 0
    for j in range(N):
        a = X[j]
        # [2**(i-1)-a,2*2**(i-1)-a),[3*2**(i-1)-a,4*2**(i-1)-a) にある Y の要素の個数を数え上げる
        r += bisect_right(Y,2*mod-a-1) - bisect_left(Y,mod-a)
        r += bisect_right(Y,4*mod-a-1) - bisect_left(Y,3*mod-a)
    if r % 2 == 1:
        ans += mod

print(ans)


Fixed submission:
import sys
from bisect import bisect_right,bisect_left
def I(): return int(sys.stdin.readline().rstrip())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))  #空白あり


N = I()
A,B = LI(),LI()

# 各桁の xor を考える

ans = 0
mod = 1 << 29
for i in range(29,0,-1):  # 2**(i-1) の位
    X = [a & (mod-1) for a in A]
    Y = [b & (mod-1) for b in B]
    X.sort()
    Y.sort(reverse=True)
    mod >>= 1
    r = 0
    i1,i2,i3 = 0,0,0
    for j in range(N):
        x = X[j]
        # [2**(i-1)-x,2*2**(i-1)-x),[3*2**(i-1)-x,4*2**(i-1)-x) にある Y の要素の個数を数え上げる
        # 尺取り法
        while i1 < N and Y[i1] >= mod-x:
            i1 += 1
        while i2 < N and Y[i2] >= 2*mod-x:
            i2 += 1
        while i3 < N and Y[i3] >= 3*mod-x:
            i3 += 1
        r += i1-i2+i3
    if r % 2 == 1:
        ans += mod

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from bisect import bisect_right,bisect_left
def I(): return int(sys.stdin.readline().rstrip())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))  #空白あり


N = I()
A,B = LI(),LI()

# 各桁の xor を考える

ans = 0
for i in range(29,0,-1):  # 2**(i-1) の位
    X = [A[j] & ((1 << i) - 1) for j in range(N)]
    Y = [B[j] & ((1 << i) - 1) for j in range(N)]
    Y.sort()
    r = 0
    for j in range(N):
        a = X[j]
        # [2**(i-1)-a,2*2**(i-1)-a),[3*2**(i-1)-a,4*2**(i-1)-a) にある Y の要素の個数を数え上げる
        r += bisect_right(Y,(1 << i) - a - 1) - bisect_left(Y,(1 << (i-1)) - a)
        r += bisect_right(Y,(1 << (i+1)) - a - 1) - bisect_left(Y,3*(1 << (i-1)) - a)
    if r % 2 == 1:
        ans += 1 << (i-1)

print(ans)


Fixed submission:
import sys
from bisect import bisect_right,bisect_left
def I(): return int(sys.stdin.readline().rstrip())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))  #空白あり


N = I()
A,B = LI(),LI()

# 各桁の xor を考える

ans = 0
mod = 1 << 29
for i in range(29,0,-1):  # 2**(i-1) の位
    X = [a & (mod-1) for a in A]
    Y = [b & (mod-1) for b in B]
    X.sort()
    Y.sort(reverse=True)
    mod >>= 1
    r = 0
    i1,i2,i3 = 0,0,0
    for j in range(N):
        x = X[j]
        # [2**(i-1)-x,2*2**(i-1)-x),[3*2**(i-1)-x,4*2**(i-1)-x) にある Y の要素の個数を数え上げる
        # 尺取り法
        while i1 < N and Y[i1] >= mod-x:
            i1 += 1
        while i2 < N and Y[i2] >= 2*mod-x:
            i2 += 1
        while i3 < N and Y[i3] >= 3*mod-x:
            i3 += 1
        r += i1-i2+i3
    if r % 2 == 1:
        ans += mod

print(ans)