Buggy python submission (verdict: Runtime Error):
import numpy as np
N,K = map(int,input().split())
A = np.int32(input().split())

d = [0]*40
for k in range(40):
    d[k] = np.sum(min(A&2**k,1))

dd = [0]*41
for k in range(40):
    dd[k] = dd[k-1]+max(d[k],N-d[k])*2**k

dp = [0]*(40)

for k in range(40):
    if K&2**k == 0:
        dp[k] = dp[k-1]+d[k]*2**k
    else:
        dp[k] = max(dp[k-1]+(N-d[k])*2**k,dd[k-1]+d[k]*2**k)

print(dp[-1])

Fixed submission:
from collections import defaultdict
N,K = map(int,input().split())
A = list(map(lambda x:bin(int(x))[2:],input().split()))
l = 0
for i in range(N):
    l = max(l,len(A[i]))
count = defaultdict(lambda:0)
for i in range(N):
    for j in range(len(A[i])):
        if A[i][-j-1] == '1':
            count[j] += 1
l = max(count.keys())

def rec(x):
    if x=='':
        return 0
    if '0' not in x:
        res = 0
        for i in range(len(x)):
            res += max(count[i],N-count[i])*2**i
        return res
    if x[0] == '1':
        return max(rec('1'*(len(x)-1))+count[len(x)-1]*2**(len(x)-1),rec(x[1:])+(N-count[len(x)-1])*2**(len(x)-1))
    else:
        return rec(x[1:])+count[len(x)-1]*2**(len(x)-1)
ans = rec(bin(K)[2:])
for i in range(len(bin(K)[2:]),l+1):
    ans += count[i]*2**i
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
N,K = map(int,input().split())
A = list(map(int,input().split()))

d = [0]*40
for a in A:
    for k in range(len(bin(a))-2):
        d[k] += min(a&2**k,1)

dd = [0]*41
for k in range(40):
    dd[k] = dd[k-1]+max(d[k],N-d[k])*2**k

dp = [0]*(40)

for k in range(40):
    if K&2**k == 0:
        dp[k] = dp[k-1]+d[k]*2**k
    else:
        dp[k] = max(dp[k-1]+(N-d[k])*2**k,dd[k-1]+d[k]*2**k)

print(dp[-1])

Fixed submission:
from collections import defaultdict
N,K = map(int,input().split())
A = list(map(lambda x:bin(int(x))[2:],input().split()))
l = 0
for i in range(N):
    l = max(l,len(A[i]))
count = defaultdict(lambda:0)
for i in range(N):
    for j in range(len(A[i])):
        if A[i][-j-1] == '1':
            count[j] += 1
l = max(count.keys())

def rec(x):
    if x=='':
        return 0
    if '0' not in x:
        res = 0
        for i in range(len(x)):
            res += max(count[i],N-count[i])*2**i
        return res
    if x[0] == '1':
        return max(rec('1'*(len(x)-1))+count[len(x)-1]*2**(len(x)-1),rec(x[1:])+(N-count[len(x)-1])*2**(len(x)-1))
    else:
        return rec(x[1:])+count[len(x)-1]*2**(len(x)-1)
ans = rec(bin(K)[2:])
for i in range(len(bin(K)[2:]),l+1):
    ans += count[i]*2**i
print(ans)

Buggy python submission (verdict: Runtime Error):
N,K = map(int,input().split())
A = list(map(int,input().split()))

d = [0]*40
for a in A:
    for k in range(len(bin(a))-1):
        d[k] += min(a&2**k,1)

dd = [0]*len(bin(K))
for k in range(len(dd)-1):
    dd[k] = dd[k-1]+max(d[k],N-d[k])*2**k

dp = [0]*(len(bin(K))-1)

for k in range(len(dp)):
    if K&2**k == 0:
        dp[k] = dp[k-1]+d[k]*2**k
    else:
        dp[k] = max(dp[k-1]+(N-d[k])*2**k,dd[k-1]+d[k]*2**k)

print(dp[-1])

Fixed submission:
from collections import defaultdict
N,K = map(int,input().split())
A = list(map(lambda x:bin(int(x))[2:],input().split()))
l = 0
for i in range(N):
    l = max(l,len(A[i]))
count = defaultdict(lambda:0)
for i in range(N):
    for j in range(len(A[i])):
        if A[i][-j-1] == '1':
            count[j] += 1
l = max(count.keys())

def rec(x):
    if x=='':
        return 0
    if '0' not in x:
        res = 0
        for i in range(len(x)):
            res += max(count[i],N-count[i])*2**i
        return res
    if x[0] == '1':
        return max(rec('1'*(len(x)-1))+count[len(x)-1]*2**(len(x)-1),rec(x[1:])+(N-count[len(x)-1])*2**(len(x)-1))
    else:
        return rec(x[1:])+count[len(x)-1]*2**(len(x)-1)
ans = rec(bin(K)[2:])
for i in range(len(bin(K)[2:]),l+1):
    ans += count[i]*2**i
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
N,K = map(int,input().split())
A = list(map(int,input().split()))

d = [0]*40
for a in A:
    for k in range(40):
        d[k] += min(a&2**k,1)

dd = [0]*41
for k in range(40):
    dd[k] = dd[k-1]+max(d[k],N-d[k])*2**k

dp = [0]*40

for k in range(40):
    if K&2**k == 0:
        dp[k] = dp[k-1]+d[k]*2**k
    else:
        dp[k] = max(dp[k-1]+(N-d[k])*2**k,dd[k-1]+d[k]*2**k)

print(dp[-1])

Fixed submission:
from collections import defaultdict
N,K = map(int,input().split())
A = list(map(lambda x:bin(int(x))[2:],input().split()))
l = 0
for i in range(N):
    l = max(l,len(A[i]))
count = defaultdict(lambda:0)
for i in range(N):
    for j in range(len(A[i])):
        if A[i][-j-1] == '1':
            count[j] += 1
l = max(count.keys())

def rec(x):
    if x=='':
        return 0
    if '0' not in x:
        res = 0
        for i in range(len(x)):
            res += max(count[i],N-count[i])*2**i
        return res
    if x[0] == '1':
        return max(rec('1'*(len(x)-1))+count[len(x)-1]*2**(len(x)-1),rec(x[1:])+(N-count[len(x)-1])*2**(len(x)-1))
    else:
        return rec(x[1:])+count[len(x)-1]*2**(len(x)-1)
ans = rec(bin(K)[2:])
for i in range(len(bin(K)[2:]),l+1):
    ans += count[i]*2**i
print(ans)

Buggy python submission (verdict: Runtime Error):
from collections import defaultdict
N,K = map(int,input().split())
K = bin(K)[2:]
A = list(map(lambda x:bin(int(x))[2:],input().split()))
count = defaultdict(lambda:0)
for i in range(N):
    for j in range(len(A[i])):
        if A[i][-j-1] == '1':
            count[j] += 1
def rec(x):
    if x=='':
        return 0
    if '0' not in x:
        res = 0
        for i in range(len(x)):
            res += max(count[i],N-count[i])*2**i
        return res
    if x[0] == '1':
        return max(rec('1'*(len(x)-1))+count[len(x)-1]*2**(len(x)-1),rec(x[1:])+(N-count[len(x)-1])*2**(len(x)-1))
    else:
        return rec(x[1:])+count[len(x)-1]*2**(len(x)-1)
ans = rec(K)
for i in range(len(K),l+1):
    ans += count[i]*2**i
print(ans)

Fixed submission:
from collections import defaultdict
N,K = map(int,input().split())
A = list(map(lambda x:bin(int(x))[2:],input().split()))
l = 0
for i in range(N):
    l = max(l,len(A[i]))
count = defaultdict(lambda:0)
for i in range(N):
    for j in range(len(A[i])):
        if A[i][-j-1] == '1':
            count[j] += 1
l = max(count.keys())

def rec(x):
    if x=='':
        return 0
    if '0' not in x:
        res = 0
        for i in range(len(x)):
            res += max(count[i],N-count[i])*2**i
        return res
    if x[0] == '1':
        return max(rec('1'*(len(x)-1))+count[len(x)-1]*2**(len(x)-1),rec(x[1:])+(N-count[len(x)-1])*2**(len(x)-1))
    else:
        return rec(x[1:])+count[len(x)-1]*2**(len(x)-1)
ans = rec(bin(K)[2:])
for i in range(len(bin(K)[2:]),l+1):
    ans += count[i]*2**i
print(ans)