Buggy python submission (verdict: Runtime Error):
ef main():
  n=int(input())
  num=[int(i) for i in input().split()]
  mod=10**9+7

  import math
  if max(num)==0:
    print(0)
    exit()
  l=math.ceil(math.log(max(num),2))

  ans=[0]*l
  tmp1,tmp2,tmp3=0,0,0
  for i in range(l):
    ans[i]=tmp3
    cnt=0
    for j in range(n):
      if (num[j]>>i)&1:
        cnt+=1
    tmp1=cnt*(n-cnt)
    tmp2=(ans[i]+tmp1)%2
    tmp3=(ans[i]+tmp1)//2
    ans[i]=tmp2

  a_append=ans.append
  while tmp3>0:
    a_append(tmp3%2)
    #print(tmp3)
    tmp3//=2
  #print(ans)
  ans=int(''.join([str(i) for i in ans[::-1]]),2)%mod
  print(ans)
  
if __name__=='__main__':
  main()

Fixed submission:
def main():
  n=int(input())
  num=[int(i) for i in input().split()]
  mod=10**9+7

  import math
  if max(num)==0:
    print(0)
    exit()
  l=math.ceil(math.log(max(num),2))

  ans=[0]*l
  tmp1,tmp2,tmp3=0,0,0
  for i in range(l):
    ans[i]=tmp3
    cnt=0
    for j in range(n):
      if (num[j]>>i)&1:
        cnt+=1
    tmp1=cnt*(n-cnt)
    tmp2=(ans[i]+tmp1)%2
    tmp3=(ans[i]+tmp1)//2
    ans[i]=tmp2

  a_append=ans.append
  while tmp3>0:
    a_append(tmp3%2)
    #print(tmp3)
    tmp3//=2
  #print(ans)
  ans=int(''.join([str(i) for i in ans[::-1]]),2)%mod
  print(ans)
  
if __name__=='__main__':
  main()

Buggy python submission (verdict: Time Limit Exceeded):
def main():
  n=int(input())
  num=[int(i) for i in input().split()]
  mod=10**9+7

  import math
  if max(num)==0:
    print(0)
    exit()
  l=math.ceil(math.log(max(num),2))

  ans=[0]*l
  tmp1,tmp2,tmp3=0,0,0
  for i in range(l):
    ans[i]=tmp3
    cnt=0
    for j in range(n):
      if (num[j]>>i)&1:
        cnt+=1
    tmp1=cnt*(n-cnt)
    tmp2=(ans[i]+tmp1)%2
    tmp3=(ans[i]+tmp1)//2
    ans[i]=tmp2

  a_append=ans.append
  while tmp3>0:
    a_append(tmp3%2)
    #print(tmp3)
    tmp3//=2
  #print(ans)
  ans=int(''.join([str(i) for i in ans[::-1]]),2)%mod
  print(ans)
  
if __name__=='__main__':
  main()


Fixed submission:
def main():
  n=int(input())
  num=[int(i) for i in input().split()]
  mod=10**9+7

  import math
  if max(num)==0:
    print(0)
    exit()
  l=math.ceil(math.log(max(num),2))

  ans=[0]*l
  tmp1,tmp2,tmp3=0,0,0
  for i in range(l):
    ans[i]=tmp3
    cnt=0
    for j in range(n):
      if (num[j]>>i)&1:
        cnt+=1
    tmp1=cnt*(n-cnt)
    tmp2=(ans[i]+tmp1)%2
    tmp3=(ans[i]+tmp1)//2
    ans[i]=tmp2

  a_append=ans.append
  while tmp3>0:
    a_append(tmp3%2)
    #print(tmp3)
    tmp3//=2
  #print(ans)
  ans=int(''.join([str(i) for i in ans[::-1]]),2)%mod
  print(ans)
  
if __name__=='__main__':
  main()

Buggy python submission (verdict: Runtime Error):
n=int(input())
num=[int(i) for i in input().split()]
mod=10**9+7

import math
l=math.ceil(math.log(max(num),2))

ans=[0]*l
tmp1,tmp2,tmp3=0,0,0
for i in range(l):
  ans[i]=tmp3
  cnt=0
  for j in range(n):
    if (num[j]>>i)&1:
      cnt+=1
  tmp1=cnt*(n-cnt)
  tmp2=(ans[i]+tmp1)%2
  tmp3=(ans[i]+tmp1)//2
  ans[i]=tmp2

while tmp3>0:
  ans.append(tmp3%2)
  #print(tmp3)
  tmp3//=2
#print(ans)
ans=int(''.join([str(i) for i in ans[::-1]]),2)%mod
print(ans)


Fixed submission:
def main():
  n=int(input())
  num=[int(i) for i in input().split()]
  mod=10**9+7

  import math
  if max(num)==0:
    print(0)
    exit()
  l=math.ceil(math.log(max(num),2))

  ans=[0]*l
  tmp1,tmp2,tmp3=0,0,0
  for i in range(l):
    ans[i]=tmp3
    cnt=0
    for j in range(n):
      if (num[j]>>i)&1:
        cnt+=1
    tmp1=cnt*(n-cnt)
    tmp2=(ans[i]+tmp1)%2
    tmp3=(ans[i]+tmp1)//2
    ans[i]=tmp2

  a_append=ans.append
  while tmp3>0:
    a_append(tmp3%2)
    #print(tmp3)
    tmp3//=2
  #print(ans)
  ans=int(''.join([str(i) for i in ans[::-1]]),2)%mod
  print(ans)
  
if __name__=='__main__':
  main()