Buggy python submission (verdict: Runtime Error):
n,k=map(int,input().split())
s=list(input())
s=list(map(int,s))
stack=[]
tmp=1
flag=True
for i in range(1,len(s)):
  if s[i]!=s[i-1]:
    stack.append(tmp)
    tmp=1
  else:
    tmp+=1
stack.append(tmp)
left=[0]
right=[0]
tmp=0
if s[0]==0:
  flag=False
  if len(stack)%2==1:
    stack.append(0)
  if len(stack)//2<=k:
    print(len(s))
    exit()
else:
  if len(stack)%2==0:
    stack.append(0)
  if len(stack)//2<=k:
    print(len(s))
    exit()
for i in range(len(stack)):
  tmp+=stack[i]
  if i%2==0:
    if flag:
      right.append(tmp)
    else:
      left.append(tmp)
  else:
    if flag:
      left.append(tmp)
    else:
      right.append(tmp)
ans=0
for i in range(len(right)-k):
  if flag:
    ans=max(ans,right[i+k+1]-left[i])
  else:
    ans=max(ans,right[i+k]-left[i])
print(ans)


Fixed submission:
n,k=map(int,input().split())
s=list(input())
s=list(map(int,s))
stack=[]
tmp=0
now=1
for i in range(n):
  if s[i]==now:
    tmp+=1
  else:
    stack.append(tmp)
    tmp=1
    now=1-now
stack.append(tmp)
if len(stack)%2==0:
  stack.append(0)
Acc=[0]*(len(stack)+1)
for i in range(len(stack)):
  Acc[i+1]=Acc[i]+stack[i]
ans=0
for i in range(0,len(stack),2):
  left = i
  right = min(i+k*2+1,len(stack))
  ans=max(ans,Acc[right]-Acc[left])
print(ans)

Buggy python submission (verdict: Runtime Error):
n,k=map(int,input().split())
s=list(input())
s=list(map(int,s))
stack=[]
tmp=1
for i in range(1,len(s)):
  if s[i]!=s[i-1]:
    stack.append(tmp)
    tmp=1
  else:
    tmp+=1
stack.append(tmp)
if s[0]==1:
  if len(s)//2<=k:
    print(len(s))
    exit()
if s[0]==0:
  if (len(s)+1)//2<=k:
    print(len(s))
    exit()
acc=[]
acc2=[]
ans=0
if s[0]==1:
  Acc=stack[0]
  Acc2=0
  acc.append(Acc)
  acc2.append(0)
  for i in range(1,len(stack)-len(stack)%2,2):
    Acc+=stack[i]
    Acc+=stack[i+1]
    acc.append(Acc)
    Acc2+=stack[i-1]
    Acc2+=stack[i]
    acc2.append(Acc2)
  if len(stack)%2==0:
    Acc2+=stack[i+1]
    Acc2+=stack[i+2]
    acc2.append(Acc2)
  if len(stack)%2==1:
    Acc+=stack[-1]
    acc.append(Acc)
    Acc2+=stack[-2]
    Acc2+=stack[-1]
    acc2.append(Acc2)
  for i in range(len(acc)-k):
    ans=max(ans,acc[i+k]-acc2[i])
if s[0]==0:
  Acc=stack[0]
  Acc2=0
  acc.append(0)
  acc.append(Acc)
  acc2.append(0)
  for i in range(1,len(stack)-1-len(stack)%2,2):
    Acc+=stack[i]
    Acc+=stack[i+1]
    acc.append(Acc)
    Acc2+=stack[i-1]
    Acc2+=stack[i]
    acc2.append(Acc2)
  if len(stack)%2==0:
    Acc2+=stack[i+1]
    Acc2+=stack[i+2]
    acc2.append(Acc2)
  if len(stack)%2==1:
    Acc+=stack[-1]
    acc.append(Acc)
    Acc2+=stack[-2]
    Acc2+=stack[-1]
    acc2.append(Acc2)
  for i in range(len(acc)-k):
    ans=max(ans,acc2[i+k]-acc[i])
print(ans)

Fixed submission:
n,k=map(int,input().split())
s=list(input())
s=list(map(int,s))
stack=[]
tmp=0
now=1
for i in range(n):
  if s[i]==now:
    tmp+=1
  else:
    stack.append(tmp)
    tmp=1
    now=1-now
stack.append(tmp)
if len(stack)%2==0:
  stack.append(0)
Acc=[0]*(len(stack)+1)
for i in range(len(stack)):
  Acc[i+1]=Acc[i]+stack[i]
ans=0
for i in range(0,len(stack),2):
  left = i
  right = min(i+k*2+1,len(stack))
  ans=max(ans,Acc[right]-Acc[left])
print(ans)

Buggy python submission (verdict: Runtime Error):
n,k=map(int,input().split())
s=list(input())
s=list(map(int,s))
stack=[]
tmp=1
for i in range(1,len(s)):
  if s[i]!=s[i-1]:
    stack.append(tmp)
    tmp=1
  else:
    tmp+=1
stack.append(tmp)
if s[0]==1:
  if len(s)//2<=k:
    print(len(s))
    exit()
if s[0]==0:
  if (len(s)+1)//2<=k:
    print(len(s))
    exit()
acc=[]
acc2=[]
ans=0
if s[0]==1:
  Acc=stack[0]
  Acc2=0
  acc.append(Acc)
  acc2.append(0)
  for i in range(1,len(stack)-len(stack)%2,2):
    Acc+=stack[i]
    Acc+=stack[i+1]
    acc.append(Acc)
    Acc2+=stack[i-1]
    Acc2+=stack[i]
    acc2.append(Acc2)
  if len(stack)%2==1:
    Acc+=stack[-1]
    acc.append(Acc)
    Acc2+=stack[-2]
    Acc2+=stack[-1]
    acc2.append(Acc2)
  for i in range(len(acc)-k-1):
    ans=max(ans,acc[i+k]-acc2[i])
if s[0]==0:
  Acc=stack[0]
  Acc2=0
  acc.append(0)
  acc.append(Acc)
  acc2.append(0)
  for i in range(1,len(stack)-len(stack)%2,2):
    Acc+=stack[i]
    Acc+=stack[i+1]
    acc.append(Acc)
    Acc2+=stack[i-1]
    Acc2+=stack[i]
    acc2.append(Acc2)
  if len(stack)%2==1:
    Acc+=stack[-1]
    acc.append(Acc)
    Acc2+=stack[-2]
    Acc2+=stack[-1]
    acc2.append(Acc2)
  for i in range(len(acc)-k-1):
    ans=max(ans,acc2[i+k]-acc[i])
print(ans)

Fixed submission:
n,k=map(int,input().split())
s=list(input())
s=list(map(int,s))
stack=[]
tmp=0
now=1
for i in range(n):
  if s[i]==now:
    tmp+=1
  else:
    stack.append(tmp)
    tmp=1
    now=1-now
stack.append(tmp)
if len(stack)%2==0:
  stack.append(0)
Acc=[0]*(len(stack)+1)
for i in range(len(stack)):
  Acc[i+1]=Acc[i]+stack[i]
ans=0
for i in range(0,len(stack),2):
  left = i
  right = min(i+k*2+1,len(stack))
  ans=max(ans,Acc[right]-Acc[left])
print(ans)

Buggy python submission (verdict: Runtime Error):
n,k=map(int,input().split())
s=list(input())
s=list(map(int,s))
stack=[]
tmp=1
for i in range(1,len(s)):
  if s[i]!=s[i-1]:
    stack.append(tmp)
    tmp=1
  else:
    tmp+=1
stack.append(tmp)
acc=[]
acc2=[]
ans=0
if s[0]==1:
  Acc=stack[0]
  Acc2=0
  acc.append(Acc)
  acc2.append(0)
  for i in range(1,len(stack)-len(stack)%2,2):
    Acc+=stack[i]
    Acc+=stack[i+1]
    acc.append(Acc)
    Acc2+=stack[i-1]
    Acc2+=stack[i]
    acc2.append(Acc2)
  if len(stack)%2==1:
    Acc+=stack[-1]
    acc.append(Acc)
    Acc2+=stack[-2]
    Acc2+=stack[-1]
    acc2.append(Acc2)
  for i in range(len(acc)-k-1):
    ans=max(ans,acc[i+k]-acc2[i])
if s[0]==0:
  Acc=stack[0]
  Acc2=0
  acc.append(0)
  acc.append(Acc)
  acc2.append(0)
  for i in range(1,len(stack)-len(stack)%2,2):
    Acc+=stack[i]
    Acc+=stack[i+1]
    acc.append(Acc)
    Acc2+=stack[i-1]
    Acc2+=stack[i]
    acc2.append(Acc2)
  if len(stack)%2==1:
    Acc+=stack[-1]
    acc.append(Acc)
    Acc2+=stack[-2]
    Acc2+=stack[-1]
    acc2.append(Acc2)
  for i in range(len(acc)-k-1):
    ans=max(ans,acc2[i+k]-acc[i])
print(ans)

Fixed submission:
n,k=map(int,input().split())
s=list(input())
s=list(map(int,s))
stack=[]
tmp=0
now=1
for i in range(n):
  if s[i]==now:
    tmp+=1
  else:
    stack.append(tmp)
    tmp=1
    now=1-now
stack.append(tmp)
if len(stack)%2==0:
  stack.append(0)
Acc=[0]*(len(stack)+1)
for i in range(len(stack)):
  Acc[i+1]=Acc[i]+stack[i]
ans=0
for i in range(0,len(stack),2):
  left = i
  right = min(i+k*2+1,len(stack))
  ans=max(ans,Acc[right]-Acc[left])
print(ans)

Buggy python submission (verdict: Runtime Error):
n,k=map(int,input().split())
s=list(input())
s=list(map(int,s))
stack=[]
tmp=1
for i in range(1,len(s)):
  if s[i]!=s[i-1]:
    stack.append(tmp)
    tmp=1
  else:
    tmp+=1
stack.append(tmp)
acc=[]
acc2=[]
ans=0
if s[0]==1:
  Acc=stack[0]
  Acc2=0
  acc.append(Acc)
  acc2.append(0)
  for i in range(1,len(stack)-len(stack)%2,2):
    Acc+=stack[i]
    Acc+=stack[i+1]
    acc.append(Acc)
    Acc2+=stack[i-1]
    Acc2+=stack[i]
    acc2.append(Acc2)
  if len(stack)%2==1:
    Acc+=stack[-1]
    acc.append(Acc)
    Acc2+=stack[-2]
    Acc2+=stack[-1]
    acc2.append(Acc2)
  for i in range(len(acc)-k):
    ans=max(ans,acc[i+k]-acc2[i])
if s[0]==0:
  Acc=stack[0]
  Acc2=0
  acc.append(0)
  acc.append(Acc)
  acc2.append(0)
  for i in range(1,len(stack)-len(stack)%2,2):
    Acc+=stack[i]
    Acc+=stack[i+1]
    acc.append(Acc)
    Acc2+=stack[i-1]
    Acc2+=stack[i]
    acc2.append(Acc2)
  if len(stack)%2==1:
    Acc+=stack[-1]
    acc.append(Acc)
    Acc2+=stack[-2]
    Acc2+=stack[-1]
    acc2.append(Acc2)
  for i in range(len(acc)-k):
    ans=max(ans,acc2[i+k]-acc[i])
print(ans)

Fixed submission:
n,k=map(int,input().split())
s=list(input())
s=list(map(int,s))
stack=[]
tmp=0
now=1
for i in range(n):
  if s[i]==now:
    tmp+=1
  else:
    stack.append(tmp)
    tmp=1
    now=1-now
stack.append(tmp)
if len(stack)%2==0:
  stack.append(0)
Acc=[0]*(len(stack)+1)
for i in range(len(stack)):
  Acc[i+1]=Acc[i]+stack[i]
ans=0
for i in range(0,len(stack),2):
  left = i
  right = min(i+k*2+1,len(stack))
  ans=max(ans,Acc[right]-Acc[left])
print(ans)