Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[pivot],A[rank] = A[rank],A[pivot]
        for row in range(rank+1,len(A)):
            if A[row][col]:
                A[row] = [A[row][j]^A[rank][j] for j in range(len(A[0]))]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

max_digit = len(format(max(A), 'b'))

use_digit = []
ans = 0
for j in range(max_digit)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        use_digit.append(j)

a = [[0]*len(use_digit) for _ in range(N)]
k = 0
for k,j in enumerate(use_digit):
    for i in range(N):
        if A[i]>>j & 1:
            a[i][k] = 1

g = F2_GaussJordan(a,False)

s = 0
for i in range(N):
    s = max(s,s^sum([g[i][j]*2**use_digit[j] for j in range(len(use_digit))]))
ans += 2*s

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[pivot],A[rank] = A[rank],A[pivot]
        for row in range(rank+1,len(A)):
            if A[row][col]:
                A[row] = [A[row][j]^A[rank][j] for j in range(len(A[0]))]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

max_digit = len(format(max(A), 'b'))

use_digit = []
ans = 0
for j in range(max_digit)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        use_digit.append(j)

a = [[0]*max_digit for _ in range(N)]
k = 0
for k,j in enumerate(use_digit):
    for i in range(N):
        if A[i]>>j & 1:
            a[i][k] = 1

g = F2_GaussJordan(a,False)

s = 0
for i in range(N):
    s = max(s,s^sum([g[i][j]*2**use_digit[j] for j in range(len(use_digit))]))
ans += 2*s

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

import numpy as np

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[[pivot,rank]] = A[[rank,pivot]]
        for row in range(rank+1,len(A)):
            if (row != rank and A[row][col]):
                A[row] ^= A[rank]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

use_digit = []
ans = 0
for j in range(60)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        use_digit.append(j)

a = np.zeros((N,len(use_digit)), dtype=bool)
k = 0
for k,j in enumerate(use_digit):
    for i in range(N):
        if A[i]>>j & 1:
            a[i][k] = 1
        else:
            a[i][k] = 0

g = F2_GaussJordan(a,False)

s = 0
for i in range(N):
    s = max(s,s^sum([g[i][j]*2**use_digit[j] for j in range(len(use_digit))]))
ans += 2*s

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[pivot],A[rank] = A[rank],A[pivot]
        for row in range(rank+1,len(A)):
            if A[row][col]:
                A[row] = [A[row][j]^A[rank][j] for j in range(len(A[0]))]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

max_digit = len(format(max(A), 'b'))

use_digit = []
ans = 0
for j in range(max_digit)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        use_digit.append(j)

a = [[0]*max_digit for _ in range(N)]
k = 0
for k,j in enumerate(use_digit):
    for i in range(N):
        if A[i]>>j & 1:
            a[i][k] = 1
        else:
            a[i][k] = 0

g = F2_GaussJordan(a,False)

s = 0
for i in range(N):
    s = max(s,s^sum([g[i][j]*2**use_digit[j] for j in range(len(use_digit))]))
ans += 2*s

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[pivot],A[rank] = A[rank],A[pivot]
        for row in range(len(A)):
            if (row != rank and A[row][col]):
                A[row] = [A[row][j]^A[rank][j] for j in range(len(A[0]))]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

max_digit = len(format(max(A), 'b'))

use_digit = []
ans = 0
for j in range(max_digit)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        use_digit.append(j)

a = [[0]*max_digit for _ in range(N)]
k = 0
for k,j in enumerate(use_digit):
    for i in range(N):
        if A[i]>>j & 1:
            a[i][k] = 1
        else:
            a[i][k] = 0

g = F2_GaussJordan(a,False)

s = 0
for i in range(N):
    s = max(s,s^sum([g[i][j]*2**use_digit[j] for j in range(len(use_digit))]))
ans += 2*s

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[pivot],A[rank] = A[rank],A[pivot]
        for row in range(len(A)):
            if (row != rank and A[row][col]):
                A[row] = [A[row][j]^A[rank][j] for j in range(len(A[0]))]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

use_digit = []
ans = 0
for j in range(60)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        use_digit.append(j)

a = [[0]*60 for _ in range(N)]
k = 0
for k,j in enumerate(use_digit):
    for i in range(N):
        if A[i]>>j & 1:
            a[i][k] = 1
        else:
            a[i][k] = 0

g = F2_GaussJordan(a,False)

s = 0
for i in range(N):
    s = max(s,s^sum([g[i][j]*2**use_digit[j] for j in range(len(use_digit))]))
ans += 2*s

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

import numpy as np

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[[pivot,rank]] = A[[rank,pivot]]
        for row in range(len(A)):
            if (row != rank and A[row][col]):
                A[row] ^= A[rank]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

use_digit = []
ans = 0
for j in range(60)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        use_digit.append(j)

a = np.zeros((N,len(use_digit)), dtype=bool)
k = 0
for k,j in enumerate(use_digit):
    for i in range(N):
        if A[i]>>j & 1:
            a[i][k] = 1
        else:
            a[i][k] = 0

g = F2_GaussJordan(a,False)

s = 0
for i in range(N):
    s = max(s,s^sum([g[i][j]*2**use_digit[j] for j in range(len(use_digit))]))
ans += 2*s

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

import numpy as np

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[[pivot,rank]] = A[[rank,pivot]]
        for row in range(len(A)):
            if (row != rank and A[row][col]):
                A[row] ^= A[rank]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

use_digit = []
ans = 0
for j in range(60)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        use_digit.append(j)

a = np.zeros((N,len(use_digit)), dtype=bool)
k = 0
for k,j in enumerate(use_digit):
    for i in range(N):
        if A[i]>>j & 1:
            a[i][k] = 1
        else:
            a[i][k] = 0

g = F2_GaussJordan(a,False)

s = np.zeros(len(use_digit),dtype=bool)
row = 0
for j in range(len(use_digit)):
    for i in range(row,N):
        if g[i][j]==1:
            s ^= g[i]
            row = i+1
            break

for j,k in enumerate(s):
    ans += k*2**(use_digit[j]+1)

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

import numpy as np

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[[pivot,rank]] = A[[rank,pivot]]
        for row in range(len(A)):
            if (row != rank and A[row][col]):
                A[row] ^= A[rank]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

use_digit = []
ans = 0
for j in range(60)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        use_digit.append(j)

a = np.zeros((N,len(use_digit)), dtype=bool)
for i in range(N):
    k = 0
    for j in use_digit:
        if A[i]>>j & 1:
            a[i][k] = 1
        else:
            a[i][k] = 0
        k += 1

g = F2_GaussJordan(a,False)

s = np.zeros(len(use_digit),dtype=bool)
row = 0
for j in range(len(use_digit)):
    for i in range(row,N):
        if g[i][j]==1:
            s ^= g[i]
            row = i+1
            break

for j,k in enumerate(s):
    ans += k*2**(use_digit[j]+1)

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

import numpy as np

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[[pivot,rank]] = A[[rank,pivot]]
        for row in range(len(A)):
            if (row != rank and A[row][col]):
                A[row] ^= A[rank]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

use_digit = []
ans = 0
for j in range(60)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        use_digit.append(j)

a = np.zeros((N,len(use_digit)), dtype=int)
for i in range(N):
    k = 0
    for j in use_digit:
        if A[i]>>j & 1:
            a[i][k] = 1
        else:
            a[i][k] = 0
        k += 1

g = F2_GaussJordan(a,False)

s = np.zeros(len(use_digit),dtype=int)
row = 0
for j in range(len(use_digit)):
    for i in range(row,N):
        if g[i][j]==1:
            s ^= g[i]
            row = i+1
            break

for j,k in enumerate(s):
    ans += k*2**(use_digit[j]+1)

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

import numpy as np

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[[pivot,rank]] = A[[rank,pivot]]
        for row in range(len(A)):
            if (row != rank and A[row][col]):
                A[row] ^= A[rank]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]
xor = format(xor,'b').zfill(60)

use_digit = []
ans = 0
for j in range(60)[::-1]:
    if xor[60-j-1] == '1':
        ans += 2**j
    else:
        use_digit.append(j)

a = np.zeros((N,len(use_digit)), dtype=int)
for i in range(N):
    binary = format(A[i], 'b').zfill(60)
    k = 0
    for j in use_digit:
        if binary[60-j-1] == '1':
            a[i][k] = 1
        else:
            a[i][k] = 0
        k += 1

g = F2_GaussJordan(a,False)

s = np.zeros(len(use_digit),dtype=int)
for i in range(N):
    for j in range(len(use_digit)):
        if g[i][j]==1:
            s ^= g[i]
            break

for k in range(len(s)):
    ans += s[k]*2**(use_digit[k]+1)

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

import numpy as np

def F2_GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[[pivot,rank]] = A[[rank,pivot]]
        for row in range(len(A)):
            if (row != rank and A[row][col]):
                A[row] ^= A[rank]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

use_digit = []
ans = 0
for j in range(60)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        use_digit.append(j)

a = np.zeros((N,len(use_digit)), dtype=int)
for i in range(N):
    k = 0
    for j in use_digit:
        if A[i]>>j & 1:
            a[i][k] = 1
        else:
            a[i][k] = 0
        k += 1

g = F2_GaussJordan(a,False)

s = np.zeros(len(use_digit),dtype=int)
for i in range(N):
    for j in range(len(use_digit)):
        if g[i][j]==1:
            s ^= g[i]
            break

for k in range(len(s)):
    ans += s[k]*2**(use_digit[k]+1)

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

import numpy as np

def GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[[pivot,rank]] = A[[rank,pivot]]
        for row in range(len(A)):
            if (row != rank and A[row][col]):
                A[row] ^= A[rank]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

digit = defaultdict(int)
use_digit = []
ans = 0
for j in range(60)[::-1]:
    if xor>>j & 1:
        ans += 2**j
    else:
        digit[j] = 1
        use_digit.append(j)

a = np.zeros((N,len(use_digit)), dtype=int)
for i in range(N):
    k = 0
    for j in range(60)[::-1]:
        if digit[j]:
            if A[i]>>j & 1:
                a[i][k] = 1
            else:
                a[i][k] = 0
            k += 1

g = GaussJordan(a,False)

s = np.zeros(len(use_digit),dtype=int)
for i in range(N):
    for j in range(len(use_digit)):
        if g[i][j]==1:
            s ^= g[i]
            break

for k in range(len(s)):
    ans += s[k]*2**(use_digit[k]+1)

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

import numpy as np

def GaussJordan(A, is_extended = False):
    rank = 0
    for col in range(len(A[0])):
        if (is_extended and col == len(A[0])-1):
            break
        pivot = -1
        for row in range(rank,len(A)):
            if A[row][col]:
                pivot = row
                break
        if pivot == -1: 
            continue
        A[[pivot,rank]] = A[[rank,pivot]]
        for row in range(len(A)):
            if (row != rank and A[row][col]):
                A[row] ^= A[rank]
        rank += 1
    return A

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]
xor = format(xor,'b').zfill(60)

digit = defaultdict(int)
use_digit = []
not_use_digit = []
for j in range(60)[::-1]:
    if xor[60-j-1] == '0':
        digit[j] = 1
        use_digit.append(j)
    else:
        not_use_digit.append(j)

a = np.zeros((N,len(use_digit)), dtype=int)
for i in range(N):
    k = 0
    for j in range(60)[::-1]:
        if digit[j]:
            if A[i]>>j & 1:
                a[i][k] = 1
            else:
                a[i][k] = 0
            k += 1

g = GaussJordan(a,False)

ans = 0
for j in not_use_digit:
    ans += 2**j

s = np.zeros(len(use_digit),dtype=int)
for i in range(N):
    for j in range(len(use_digit)):
        if g[i][j]==1:
            s ^= g[i]
            break

for k in range(len(s)):
    ans += s[k]*2**(use_digit[k]+1)

print(ans)

Fixed submission:
import sys
import math
from collections import defaultdict

sys.setrecursionlimit(10**7)
def input():
    return sys.stdin.readline()[:-1]

mod = 10**9 + 7

def I(): return int(input())
def II(): return map(int, input().split())
def III(): return list(map(int, input().split()))
def Line(N):
    read_all = [tuple(map(int, input().split())) for _ in range(N)]
    return map(list,zip(*read_all))

#################

N = I()
A = III()

xor = 0
for i in range(N):
    xor ^= A[i]

for i in range(N):
    A[i] &= ~xor

max_digit = len(format(max(A), 'b'))
rank = 0
for col in range(max_digit)[::-1]:
    pivot = -1
    for row in range(rank,N):
        if A[row]>>col & 1:
            pivot = row
            break
    if pivot == -1: 
        continue
    A[pivot],A[rank] = A[rank],A[pivot]
    for row in range(rank+1,N):
        if A[row]>>col & 1:
            A[row] ^= A[rank]
    rank += 1

val = 0
for i in range(N):
    val = max(val,val^A[i])

print(2*val + xor)