qyliang/CodeNanoFix huggingface dataset:
Buggy code:
from collections import deque
import sys

def fnw(n,s):
    sm=deque([])
    if n<=len(s):
        for _ in range(n):
            sm.append(s.popleft())
    return ''.join(sm)

def jfws(s):
    fws=fnw(5,s)
    if fws=='dream':
        fws=fnw(2,s)
        if fws=='er':
            if s[0]=='a':
                s.extendleft(deque(reversed(list(fws))))
        else:
            s.extendleft(deque(reversed(list(fws))))
        return False
    elif fws=='erase':
        fws=fnw(1,s)
        if fws!='r':
            s.appendleft(fws)
        return False
    else:
        return True 

def main(s):
    while not s:
        if jfws(s):
            return 'NO'
    return 'YES'

s=deque(sys.stdin.readline().strip())
print(main(s))



Fixed code:
from collections import deque
import sys

def fnw(n,s):
    sm=deque([])
    if n<=len(s):
        for _ in range(n):
            sm.append(s.popleft())
    return sm

def jfws(s):
    # print(s)
    sm=fnw(5,s)
    # print(sm)
    if ''.join(sm)=='dream':
        sm=fnw(2,s)
        if ''.join(sm)=='er':
            if bool(s):
                if s[0]=='a':
                    s.extendleft(deque(reversed(list(sm))))
        else:
            s.extendleft(deque(reversed(list(sm))))
        return False
    elif ''.join(sm)=='erase':
        sm=fnw(1,s)
        if ''.join(sm)!='r':
            s.extendleft(sm)
        return False
    else:
        return True 

def main(s):
    while len(s)>0:
        if jfws(s):
            return 'NO'
    return 'YES'

s=deque(sys.stdin.readline().strip())
print(main(s))
Buggy code:
S = list(input())
while True:
  if len(S) >= 5:
    if S[:5] == ["d", "r", "e", "a", "m"]:
      del S[:5]
    elif S[:5] == ["e", "r", "a", "s", "e"]:
      del S[:5]
    elif S[:6] == ["e", "r", "a", "s", "e", "r"]:
      del S[:6]
    elif S[:7] == ["d", "r", "e", "a", "m", "e", "r"]:
      del S[:7]
    else:
      print("NO")
      break
  elif len(S) == 0:
    print("YES")
    break
  else:
    print("NO")
    break


Fixed code:
S = list(input())
while True:
  if len(S) >= 8:
    if S[:8] == ["d", "r", "e", "a", "m", "e", "r", "a"]:
      del S[:5]
    elif S[:7] == ["d", "r", "e", "a", "m", "e", "r"]:
      del S[:7]
    elif S[:6] == ["e", "r", "a", "s", "e", "r"]:
      del S[:6]
    elif S[:5] == ["d", "r", "e", "a", "m"]:
      del S[:5]
    elif S[:5] == ["e", "r", "a", "s", "e"]:
      del S[:5]
    else:
      print("NO")
      break
  elif len(S) == 7:
    if S[:7] == ["d", "r", "e", "a", "m", "e", "r"]:
      del S[:7]
  elif len(S) == 6:
    if S[:6] == ["e", "r", "a", "s", "e", "r"]:
      del S[:6]
  elif len(S) == 5:
    if S[:5] == ["d", "r", "e", "a", "m"]:
      del S[:5]
    elif S[:5] == ["e", "r", "a", "s", "e"]:
      del S[:5]
  elif len(S) == 0:
    print("YES")
    break
  else:
    print("NO")
    break
Buggy code:
s = input()
lst = ["eraser","erase","dreamer","dream"]
for w in lst:
    s.replace(w,"")
    
if len(s) == 0:
    ans = "YES"
else:
    ans = "NO"

print(ans)


Fixed code:
s = input()
lst = ["eraser","erase","dreamer","dream"]
for w in lst:
    s = s.replace(w,"")

if len(s) == 0:
    ans = "YES"
else:
    ans = "NO"

print(ans)
Buggy code:
print("YES" if len(input().replace("dreamer", "").replace("eraser", "").replace(
    "dream", "").replace("erase", "")) == 0 else "NO")

Fixed code:
print("YES" if len(input().replace("eraser", "").replace("erase", "").replace("dreamer", "").replace(
    "dream", "")) == 0 else "NO")
Buggy code:
s = input()

while(1):
    if len(s) == 0:
        print('YES')
        break
    if s.startswith('dreamer') :
        s = s[7:]
    elif s.startswith('eraser'):
        s = s[6:]
    elif s.startswith('dream') or s.startswith('erase'):
        s = s[5:]
    else:
        print('NO')
        break

Fixed code:
s = input()

while(1):
    if len(s) == 0:
        print('YES')
        break
    if s.endswith('dreamer') :
        s = s[:-7]
    elif s.endswith('eraser'):
        s = s[:-6]
    elif s.endswith('dream') or s.endswith('erase'):
        s = s[:-5]
    else:
        print('NO')
        break
Buggy code:
s=input()
ans=1
i=0
while 1:
  if i>=len(s):
    break
  elif i>=len(s)-4:
    ans=0
    break
  if s[i:i+5]=="dream":
    if s[i:i+7]=="dreamer":
      i+=7
    else:
      i+=5
  elif s[i:i+5]=="erase":
    if s[i:i+6]=="eraser":
      i+=6
    else:
      i+=5
  else:
    ans=0
    break
if ans:
  print("YES")
else:
  print("NO")

Fixed code:
s=input()
ans=1
i=0
while 1:
  if i>=len(s):
    break
  if s[i:i+5]=="dream":
    i+=5
  elif s[i:i+5]=="erase":
    if s[i:i+6]=="eraser":
      i+=6
    else:
      i+=5
  elif s[i-5:i+2]=="dreamer":
    i+=2
  else:
    ans=0
    break
if ans:
  print("YES")
else:
  print("NO")
Buggy code:
from sys import stdin

s = stdin.readline().rstrip()

s.replace("eraser", "").replace("erase", "").replace("dreamer", "").replace("dream", "")

if s == "":
    print("YES")
else:
    print("NO")

Fixed code:
from sys import stdin

s = stdin.readline().rstrip().replace("eraser", "").replace("erase", "").replace("dreamer", "").replace("dream", "")

if s == "":
    print("YES")
else:
    print("NO")
Buggy code:
import sys

if __name__ == '__main__':
    S = sys.stdin.readline().rstrip()

    ls = ['dream', 'dreamer', 'erase', 'eraser']
    lenS = len(S)
    dp = [False for i in range(lenS + 10)]

    dp[0] = True

    for i in range(lenS):
        print([1 if d else 0 for d in dp])
        if not dp[i]:
            continue

        for w in ls:
            if S[i:i+len(w)] == w:
                dp[i+len(w)] = True

    r = 'YES' if dp[len(S)] else 'NO'

    print(r)


Fixed code:
import sys

if __name__ == '__main__':
    S = sys.stdin.readline().rstrip()

    ls = ['dream', 'dreamer', 'erase', 'eraser']
    lenS = len(S)
    dp = [False for i in range(lenS + 10)]

    dp[0] = True

    for i in range(lenS):
        if not dp[i]:
            continue

        for w in ls:
            if S[i:i+len(w)] == w:
                dp[i+len(w)] = True

    r = 'YES' if dp[len(S)] else 'NO'

    print(r)
Buggy code:
S = input()
A = "".join(list(reversed(S)))
print(A)
i = 0

while i != len(S):
    if A[i:i+5] == "maerd":
        i += 5
    elif A[i:i+5] == "esare":
        i += 5
    elif A[i:i+7] == "remaerd":
        i += 7
    elif A[i:i+6] == "resare":
        i += 6
    else:
        print("NO")
        exit()
print("YES")

Fixed code:
S = input()
A = "".join(list(reversed(S)))
i = 0

while i != len(S):
    if A[i:i+5] == "maerd":
        i += 5
    elif A[i:i+5] == "esare":
        i += 5
    elif A[i:i+7] == "remaerd":
        i += 7
    elif A[i:i+6] == "resare":
        i += 6
    else:
        print("NO")
        exit()
print("YES")
Buggy code:
import re
def main():
    s = input()
    pattern = "^(dream|dreamer|erase|eraser)+$"
    if re.match(pattern,s):
        print('YES')
    else:
        print('No')

if __name__ == '__main__':
    main()

Fixed code:
import re
def main():
    s = input()
    pattern = "^(dream|dreamer|erase|eraser)+$"
    if re.match(pattern,s):
        print('YES')
    else:
        print('NO')

if __name__ == '__main__':
    main()
Buggy code:
s = input()
s = s.replace('erase','')
s = s.replace('eraser','')
s = s.replace('dream','')
s = s.replace('dreamer','')
if s:
    print('YES')
else:
    print('NO')

Fixed code:
s = input().replace("eraser", "").replace("erase", "").replace("dreamer", "").replace("dream", "")
print("NO" if s else "YES")
Buggy code:
# coding: utf-8
# Your code here!
s = input()

word_list = ["dreamer","dream","eraser","erase"]
for i in word_list:
    s = s.replace(i,".")

if len(set(s)) == 1:
    print("YES")
else:
    print("NO")

Fixed code:
# coding: utf-8
# Your code here!
s = input()

word_list = ["eraser","erase","dreamer","dream"]
for i in word_list:
    s = s.replace(i,".")

if len(set(s)) == 1:
    print("YES")
else:
    print("NO")
Buggy code:
S=input()
str_list=["dreamer","eraser","dream","erase"]
     
S_tmp=""
while True:
  S_tmp=S
  for str in str_list:
    if S[-len(str):]==str:
      S=S.rstrip(str)
        
  if S_tmp==S:
    break    
        
if S=="":
  print("YES")
if S!="":
  print("NO")  

Fixed code:
S=input()
str_list=["dreamer","eraser","dream","erase"]
     
while True:
  S_tmp=S
  for str in str_list:
    if S[-len(str):]==str:
      S=S[0:len(S)-len(str)]
        
  if S_tmp==S:
    break    
        
if S=="":
  print("YES")
if S!="":
  print("NO")
Buggy code:
S = input()
S_r = S[::-1]
dire = ['dream','dreamer','erase','eraser']
dire_r = [0]*4
for i in range(4):
    tmp = dire[i]
    dire_r[i] = tmp[::-1]
ind = 0

excep = 0
while ind  <len(S_r):
    if excep == 1:
        break
    for j in range(4):
        for k in range(len(dire_r[j])):
            if ind + k < len(S_r):
                tmp = dire_r[j]
                if S_r[ind+k] != tmp[k]:
                    flag = 0
                    if j == 3:
                        excep = 1
                        break

                elif k== len(dire_r[j])  -1:
                    ind = ind + len(dire_r[j])
                    print(len(dire_r[j]))
                    flag = 1
                    break

if flag == 1:
    print('YES')
else:
    print('NO')


Fixed code:
S = input()
S_r = S[::-1]
dire = ['dream','dreamer','erase','eraser']
dire_r = [0]*4
for i in range(4):
    tmp = dire[i]
    dire_r[i] = tmp[::-1]
ind = 0

excep = 0

while ind  <len(S_r):
    if excep == 1:
        break
    flag2= 0
    for j in range(4):
        if flag2 ==0:
            case = 0
            for k in range(len(dire_r[j])):
                tmp = dire_r[j]

                if ind + k < len(S_r) and case == 0:
                #    print(j)
            #        print('S:'+S_r[ind+k])
            #        print('dire:'+tmp[k])
                    if S_r[ind+k] != tmp[k]:
                        flag = 0
                        case = 1
                        if j == 3:
                            excep = 1

                    elif k== len(dire_r[j])  -1:
                        ind = ind + len(dire_r[j])
                        flag = 1
                        case = 1
                        flag2 = 1


if flag == 1:
    print('YES')
else:
    print('NO')
Buggy code:
S=input()

for i in range(10000):
  if S[-6:]=="dreamer" or S[-6:]=="eraser":
    S=S[:-6]
  elif S[-5:]=="dream" or S[-5:]=="erase":
    S=S[:-5]
  else:
    pass
  if S=[]:
    print("YES")
    break
else:
  print("NO")

Fixed code:
S=input()

for i in range(100000):
  if S[-7:]=="dreamer":
    S=S[:-7]
  elif S[-6:]=="eraser":
    S=S[:-6]
  elif S[-5:]=="dream" or S[-5:]=="erase":
    S=S[:-5]
  else:
    pass
  if S=="":
    print("YES")
    break
else:
  print("NO")
Buggy code:
if input().replace('dream','').replace('dreamer','').replace('erase','').replace('eraser','') == '': print('YES')
else: print('NO')

Fixed code:
if input().replace('eraser','').replace('erase','').replace('dreamer','').replace('dream','') == '': print('YES')
else: print('NO')
Buggy code:
s = input()
n_s = len(s)
S = ''
for i in range(n_s):
    S += s[-i-1]
words = ["maerd", "remaerd", "esare", "resare"]
cnt = 0
result = 'Yes'
print(S)
while True:
    
    if S[cnt:cnt+5] == 'maerd':
        cnt += 5
    elif S[cnt:cnt+5] == 'esare':
        cnt += 5
    elif S[cnt:cnt+6] == 'resare':
        cnt += 6
    elif S[cnt:cnt+7] == 'remaerd':
        cnt += 7
    else:
        result = 'No'
        break
    if cnt == n_s:
        break
print(result)

Fixed code:
s = input()
n_s = len(s)
S = ''
for i in range(n_s):
    S += s[-i-1]
words = ["maerd", "remaerd", "esare", "resare"]
cnt = 0
result = 'YES'
while True:
    if S[cnt:cnt+5] == 'maerd':
        cnt += 5
    elif S[cnt:cnt+5] == 'esare':
        cnt += 5
    elif S[cnt:cnt+6] == 'resare':
        cnt += 6
    elif S[cnt:cnt+7] == 'remaerd':
        cnt += 7
    else:
        result = 'NO'
        break
    if cnt == n_s:
        break
print(result)
Buggy code:
S = input()[::-1]

dreams = ['dream', 'dreamer', 'erase', 'eraser']
dreams = [dream[::-1] for dream in dreams]

i = 0
while i < len(S):
    flag = False
    for j in dreams:
        if S[i:i+len(j)] == j:
            print(S[i:i+len(j)], j)
            print(i)
            i = i + len(j)
            flag = True
    if not flag:
        break

print("YES" if flag else "NO")


Fixed code:
S = input()[::-1]

dreams = ['dream', 'dreamer', 'erase', 'eraser']
dreams = [dream[::-1] for dream in dreams]

i = 0
while i < len(S):
    flag = False
    for j in dreams:
        if S[i:i+len(j)] == j:
            i = i + len(j)
            flag = True
    if not flag:
        break

print("YES" if flag else "NO")
Buggy code:
import sys

t = set('dream, dreamer, erase, eraser'.split(', '))

def obtainable(s):
  while True:
    for i in range(5, 8):
      if s[-i:] in t:
        s = s[:-i]
        break
    else:
      return False
    if not s:
      return True
    
s = sys.stdin.readline().rstrip()

def main():
  print(t)
  print("YES" if obtainable(s) else "NO")

if __name__ ==  '__main__':
  main()

Fixed code:
import sys

t = set('dream, dreamer, erase, eraser'.split(', '))

def obtainable(s):
  while True:
    for i in range(5, 8):
      if s[-i:] in t:
        s = s[:-i]
        break
    else:
      return False
    if not s:
      return True
    
s = sys.stdin.readline().rstrip()

def main():
  print("YES" if obtainable(s) else "NO")

if __name__ ==  '__main__':
  main()
Buggy code:
s = input()
n = len(s) // 5
for i in range(n + 1):
   if len(s) == 0:
      print('YES')
      exit()
   if s[:5] == 'erase':
      s = s[5:]
   elif s[:6] == 'easer':
      s = s[6:]
   elif (s[:6] == 'dreamer') and ((s[:10] != 'dreamerase') or (s[:11] != 'dreameraser')):
      s = s[6:]
   elif (s[:5] == 'dream'):
      s = s[5:]
   else:
      print('NO')
      exit()

Fixed code:
s = input()
n = len(s) // 5
for i in range(n + 1):
   if len(s) == 0:
      print('YES')
      exit()
   if s[:6] == 'eraser':
      s = s[6:]
   elif s[:5] == 'erase':
      s = s[5:]
   elif ((s[:7] == 'dreamer') and (s[:10] != 'dreamerase') and (s[:11] != 'dreameraser')) or ((len(s) == 7) and (s == 'dreamer')):
      s = s[7:]
   elif (s[:5] == 'dream'):
      s = s[5:]
   else:
      print('NO')
      exit()
Buggy code:
s = input().replace("eraser","").replace("erase","").replace("dreamer","").replace("dream","")

if s :
    print("YES")
else:
    print("NO")

Fixed code:
s = input().replace("eraser","").replace("erase","").replace("dreamer","").replace("dream","")

if s :
    print("NO")
else:
    print("YES")
Buggy code:
# -*- coding: utf-8 -*-

I = "dream dreamer erase eraser".split()
I2 = input()

if I2.replace(I[1], "").replace(I[0], "").replace(I[3], "").replace(I[2], "").strip() == "":
  print("YES")
else:
  print("NO")

Fixed code:
# -*- coding: utf-8 -*-
 
I = ["dream", "dreamer", "erase", "eraser"]
I2 = input()
 
if I2.replace(I[1], "").replace(I[0], "").replace(I[3], "").replace(I[2], "").strip() == "":
  print("YES")
elif I2.replace(I[0], "").replace(I[2], "").replace(I[1], "").replace(I[3], "").strip() == "":
  print("YES")
elif I2.replace(I[2], "").replace(I[0], "").replace(I[3], "").replace(I[1], "").strip() == "":
  print("YES")
elif I2.replace(I[3], "").replace(I[2], "").replace(I[1], "").replace(I[0], "").strip() == "":
  print("YES")
else:
  print("NO")
Buggy code:
s=input()
n=len(s)
dp=[False]*(n+1)
dp[1]=True
c=["dream","dreamer","erase","eraser"]
for i in range(n+1):
    if dp[i]:
        l=""
        if i+5<=n:
            for idx in range(5):
                l+=s[i+idx-1]
            if l in c:
                dp[i+5]=True
        if i+6<=n:
            l+=s[i+4]
            if l in c:
                dp[i+6]=True
        if i+7<=n:
            l+=s[i+5]
            if l in c:
                dp[i+7]=True
#print(dp)
if dp[n]:
    print("YES")
else:
    print("NO")

Fixed code:
s=input()
n=len(s)
dp=[False]*(n+1)
c=["dream","dreamer","erase","eraser"]
if s[:5] in c:
    dp[5]=True
if s[:6] in c:
    dp[6]=True
if s[:7] in c:
    dp[7]=True
for i in range(n+1):
    if dp[i]:
        l=""
        if i+5<=n:
            for idx in range(5):
                l+=s[i+idx]
            if l in c:
                dp[i+5]=True
        if i+6<=n:
            l+=s[i+5]
            if l in c:
                dp[i+6]=True
        if i+7<=n:
            l+=s[i+6]
            if l in c:
                dp[i+7]=True
#print(dp)
if dp[n]:
    print("YES")
else:
    print("NO")
Buggy code:
#!/usr/bin/env python3
#%% for atcoder uniittest use
import sys
input= lambda: sys.stdin.readline().rstrip()
sys.setrecursionlimit(10**9)
def pin(type=int):return map(type,input().split())
def tupin(t=int):return tuple(pin(t))
def lispin(t=int):return list(pin(t))
#%%code
import random
def resolve():
    
    S=input()
    A="dream dreamer erase eraser".split()
    #print(A)
    que=[S]
    while(que!=[]):
        t=len(que)
        print(t)
        vS=que.pop(random.randint(0,t-1))
        if vS=="":
            print("YES")
            return
        for w in A:
            r=len(w)
            if vS[:r]==w:
                que.append(vS[r:])
        print(que,"k")    

    print("NO")
#%%submit!
resolve()

Fixed code:
#!/usr/bin/env python3
#%% for atcoder uniittest use
import sys
input= lambda: sys.stdin.readline().rstrip()
sys.setrecursionlimit(10**9)
def pin(type=int):return map(type,input().split())
def tupin(t=int):return tuple(pin(t))
def lispin(t=int):return list(pin(t))
#%%code
import random
def resolve():
    
    S=input()
    A="dream dreamer erase eraser".split()
    #print(A)
    que=[S]
    while(que!=[]):
        t=len(que)
        #print(t)
        vS=que.pop(random.randint(0,t-1))
        if vS=="":
            print("YES")
            return
        for w in A:
            r=len(w)
            if vS[:r]==w:
                que.append(vS[r:])
        #print(que,"k")    

    print("NO")
#%%submit!
resolve()
Buggy code:
s=input()
# dream dreamer erase eraser 
while len(s)>0:
	if (s[-1]=="r") & (s[-7]=="dreamer"):
		s.rstrip("dreamer")
	elif (s[-1]=="r") & (s[-6]=="eraser"):
		s.rstrip("eraser")
	elif (s[-1]=="e") & (s[-5]=="erase"):
		s.rstrip("erase")
	elif (s[-1]=="m") & (s[-5]=="dream"):
		s.rstrip("dream")
	else:
		break
		
if len(s)>0:
	print("YES")
else:
	print("NO")

Fixed code:
s=input()
# dream dreamer erase eraser 
while len(s)>0:
	if (s[-1]=="r") & (s[-7:]=="dreamer"):
		s=s[:-7]
	elif (s[-1]=="r") & (s[-6:]=="eraser"):
		s=s[:-6]
	elif (s[-1]=="e") & (s[-5:]=="erase"):
		s=s[:-5]
	elif (s[-1]=="m") & (s[-5:]=="dream"):
		s=s[:-5]
	else:
		break

if len(s)==0:
	print("YES")
else:
	print("NO")
Buggy code:
# -*- coding: utf-8 -*-

def solve(S):
    S.replace("eraser", "").replace("erase", "").replace("dream", "").replace("dreamer", "")
    if(S==""):
        print("YES")
    else:
        print("NO")
    
if __name__ == '__main__':
    S = input()
  
    solve(S)

Fixed code:
# -*- coding: utf-8 -*-

def solve(S):
    s = S.replace("eraser", "").replace("erase", "").replace("dreamer", "").replace("dream", "")

    if(s==""):
        print("YES")
    else:
        print("NO")
    
if __name__ == '__main__':
    S = input()
  
    solve(S)
Buggy code:
s = input()

# t = ['dream', 'dreamer', 'erase', 'eraser']

s = s[::-1]
for i in range(4):
    t[i] = t[i][::-1]

# print(s,t)

tmp = s

while tmp != '':
    d = tmp[:5] == 'maerd'
    dr = tmp[:7] == 'remaerd'
    e = tmp[:5] == 'esare'
    er = tmp[:6] == 'resare'
    # print(tmp[:5])
    # print(d,dr,e,er)

    if d:
        tmp = tmp[5:]
    elif e:
        tmp = tmp[5:]
    elif dr:
        tmp = tmp[7:]
    elif er:
        tmp = tmp[6:]
    else:
        print('NO')
        break

if tmp == '':
    print('YES')


Fixed code:
s = input()

# t = ['dream', 'dreamer', 'erase', 'eraser']

s = s[::-1]
# for i in range(4):
#     t[i] = t[i][::-1]

# print(s,t)

tmp = s

while tmp != '':
    d = tmp[:5] == 'maerd'
    dr = tmp[:7] == 'remaerd'
    e = tmp[:5] == 'esare'
    er = tmp[:6] == 'resare'
    # print(tmp[:5])
    # print(d,dr,e,er)

    if d:
        tmp = tmp[5:]
    elif e:
        tmp = tmp[5:]
    elif dr:
        tmp = tmp[7:]
    elif er:
        tmp = tmp[6:]
    else:
        print('NO')
        break

if tmp == '':
    print('YES')
Buggy code:
if input().replace("dream","").replace("dreamer","").replace("erase","").replace("eraser","")=="":
  print("YES")
else:
  print("NO")

Fixed code:
s=input().replace("eraser", "").replace("erase", "").replace("dreamer", "").replace("dream", "")
if s:
    print("NO")
else:
    print("YES")
Buggy code:
def h(temp):
    if temp[0] == "m":
        a = 0
    elif temp[0] == "r":
        if temp[2] == "m":
            a = 1
        else:
            a = 3
    else:
        a = 2
    return a 

def H(temp,y,a):
    c = 0
    if a == 0 or a == 2:
        for j in range(5):
            if y[a][4-j] != temp[0]:
                return c
            temp.remove(temp[0])
        c = 1
    else:
        for j in range(7):
            if y[a][6-j] != temp[j]:
                break
        c = 1
    return c,temp


s = input()
y = ['dream','dreamer','erase','eraser'] 
temp = []
t = []
k = len(s)
for i in range(k):
    temp.append(s[k-i-1])
a = h(temp)
c = 1

while len(temp) != 0 and c == 1:
    c = H(temp,y,a)
    a = h(temp)
if c[0] == 1:
    print("YES")
else :
    print("NO")

Fixed code:
def h(temp):
    if temp[0] == "m":
        a = 0
    elif temp[0] == "r":
        if temp[2] == "m":
            a = 1
        else:
            a = 3
    else:
        a = 2
    return a 

def H(temp,y,a):
    c = 0
    if a == 0 or a == 2:
        for j in range(5):
            if y[a][4-j] != temp[0]:
                return c
            temp.remove(temp[0])
        c = 1
    elif a == 3:
        for j in range(6):
            if y[a][5-j] != temp[0]:
                return c
            temp.remove(temp[0])
        c = 1
    else:
        for j in range(7):
            if y[a][6-j] != temp[0]:
                return c
            temp.remove(temp[0])
        c = 1
    return c


s = input()
y = ['dream','dreamer','erase','eraser'] 
temp = []
t = []
k = len(s)
for i in range(k):
    temp.append(s[k-i-1])
c = 1
while len(temp) != 0 and c == 1:
    a = h(temp)
    c = H(temp,y,a)
if c == 1:
    print("YES")
else :
    print("NO")
Buggy code:
import sys
input = sys.stdin.readline

def main():
    s = input()
    s = s[::-1]
    flag = True
    i = 0

    while i < len(s) - 1:
        if s[i:i + 5] == 'maerd' or s[i:i + 5] == 'esare':
            i += 5
        elif s[i:i + 6] == 'resare':
            i += 6
        elif s[i:i + 7] == 'remaerd':
            i += 7
        else:
            flag = False
            break
    print('YES' if flag else 'NO')

if __name__ == '__main__':
    main()


Fixed code:
import sys
input = lambda: sys.stdin.readline().rstrip()

def main():
    s = input()
    s = s[::-1]
    flag = True

    i = 0
    while i < len(s):
        if s[i:i + 5] == 'maerd' or s[i:i + 5] == 'esare':
            i += 5
        elif s[i:i + 6] == 'resare':
            i += 6
        elif s[i:i + 7] == 'remaerd':
            i += 7
        else:
            flag = False
            break
    print('YES' if flag else 'NO')

if __name__ == '__main__':
    main()
Buggy code:
def DFS(S):
    word_list = ["dreamer", "dream", "eraser", "erase"]
    stack = ["dream", "dreamer", "erase", "eraser"]
    while stack:
        word = stack.pop()
        if word == S[0]:
            return "YES"
        for i in word_list:
            next_word = word + i
            check = S[0][:len(word + i)]
            if next_word != check:
                continue
            if next_word == check:
                stack.append(next_word)
                print(stack)
    return "NO"

Fixed code:
def DFS(S):
    word_list = ["dreamer", "dream", "eraser", "erase"]
    stack = ["dream", "dreamer", "erase", "eraser"]
    while stack:
        word = stack.pop()
        if word == S[0]:
            return "YES"
        for i in word_list:
            next_word = word + i
            check = S[0][:len(word + i)]
            if next_word != check:
                continue
            if next_word == check:
                stack.append(next_word)
    return "NO"
 
 
 
 
 
 
if __name__ == "__main__":
    S = [input()]
    print(DFS(S))