qyliang/CodeNanoFix huggingface dataset:
Buggy code:
s=input()
n=len(s)
i=1
for j in range(n):
    if s[-i:-i-5:-1]=="maerd":
        i+=5
 
    if s[-i:-i-5:-1]=="esare":
        i+=5

    if s[-i:-i-6:-1]=="resare":
        i+=6

    if s[-i:-i-7:-1]=="remeard":
        i+=7
        
    if i==n+1:
        print("YES")
        break

if i !=n:
    print("NO")

Fixed code:
s=input()
n=len(s)
i=1
for j in range(n):
    if s[-i:-i-5:-1]=="maerd":
        i+=5
 
    if s[-i:-i-5:-1]=="esare":
        i+=5

    if s[-i:-i-6:-1]=="resare":
        i+=6

    if s[-i:-i-7:-1]=="remaerd":
        i+=7

    if i==n+1:
        print("YES")
        break

if i != n+1:
    print("NO")
Buggy code:
s = input()
s2 = s.split('eraser')
s3 = ''.join(s2).split('erase')
s4 = ''.join(s3).split('dreamer')
s5 = ''.join(s4).split('dream')

if len(s5) == 1 and s5[0] == '':
  print("YES")
else:
  print("NO")

Fixed code:
s = input()
s2 = s.split('eraser')
s3 = ''.join(s2).split('erase')
s4 = ''.join(s3).split('dreamer')
s5 = ''.join(s4).split('dream')
s5 = list(set(s5))
if len(s5) == 1 and s5[0] == '':
  print("YES")
else:
  print("NO")
Buggy code:
S = input()
divide = ["dream", "dreamer", "erase", "eraser"]
S = S[::-1]
divide = [divide[i][::-1] for i in range(4)]

while len(S) > 0:
    for i in range(4):
        if S[:len(divide[i])] == divide[i]:
            flag = "YES"
            S = S[len(divide[i]):]
            break
        else:
            flag = "NO"

print(flag)

Fixed code:
S = input()
divide = ["dream", "dreamer", "erase", "eraser"]
S = S[::-1]
divide = [divide[i][::-1] for i in range(4)]
 
while len(S) > 0:
    for i in range(4):
        if S[:len(divide[i])] == divide[i]:
            flag = "YES"
            S = S[len(divide[i]):]
            break
        else:
            flag = "NO"
    if flag == "NO":
        break

print(flag)
Buggy code:
s = input()
a = s

for i in range(10**4):
    a = a.replace('erase', '').replace('eraser', '').replace('dreamer', '').replace('dream', '')

if a == '':
    print('YES')
else:
    print('NO')


Fixed code:
s = input()
a = s

for i in range(10**4):
    a = a.replace('eraser', '').replace('erase', '').replace('dreamer', '').replace('dream', '')

if a == '':
    print('YES')
else:
    print('NO')
Buggy code:
s=input()
if s=='erasedream':
  exit()
s=s.split('eraser')
if s.count('')>0:
  s.remove('')
s=''.join(s)
s=s.split('erase')
if s.count('')>0:
  s.remove('')
s=''.join(s)
s=s.split('dreamer')
if s.count('')>0:
  s.remove('')
s=''.join(s)
s=s.split('dream')
if s.count('')>0:
  s.remove('')
s=''.join(s)
if s=='':
  print('YES')
else:
  print('NO')

Fixed code:
s=input()
s=s.split('eraser')
if s.count('')>0:
  s.remove('')
s=''.join(s)
s=s.split('erase')
if s.count('')>0:
  s.remove('')
s=''.join(s)
s=s.split('dreamer')
if s.count('')>0:
  s.remove('')
s=''.join(s)
s=s.split('dream')
if s.count('')>0:
  s.remove('')
s=''.join(s)
if s=='':
  print('YES')
else:
  print('NO')
Buggy code:
s=input()
f=0
l=['dream' ,'dreamer', 'erase','eraser']
while(f==0):
    if(s[:7] in l):
        s=s[7:]
    elif(s[:6] in l):
        s=s[6:]
    elif(s[:5] in l):
        s=s[5:]
    else:
        f=1
    
if(len(s)==0):
    print("YES")
else:
    print("NO")


Fixed code:
s=input()
s=s[::-1]
f=0
l=['dream' ,'dreamer', 'erase','eraser']
l=[c[::-1] for c in l]
while(f==0):
    if(s[:7] in l):
        s=s[7:]
    elif(s[:6] in l):
        s=s[6:]
    elif(s[:5] in l):
        s=s[5:]
    else:
        f=1
if(len(s)==0):
    print("YES")
else:
    print("NO")
Buggy code:
S = input()
day_dream_word = ["eraser", "erase", "dreamer", "dream"]
for replace_word in day_dream_word:
  S.replace(replace_word, "")
if S == "":
  print('YES')
else:
  print('NO')

Fixed code:
S = input()
day_dream_word = ["eraser", "erase", "dreamer", "dream"]
for replace_word in day_dream_word:
  S = S.replace(replace_word, "")

if S == "":
  print('YES')
else:
  print('NO')
Buggy code:
def main():
    Ss = input()
    S = list(Ss)
    now = 0
    T = ''
    Sr = []
    for i in range(1,len(S)+1):
        Sr[-i] = S[i-1]

    while True:
        tmp5 = Sr[now:now+5]
        tmp6 = Sr[now:now+6]
        tmp7 = Sr[now:now+7]
        if tmp5[0] == 'e' and tmp5 == ['e','s','a','r','e']:
            T += 'erase'
            now += 5
        elif tmp5[0] == 'm' and tmp5 == ['m','a','e','r','d']:
            T += 'dream'
            now += 5
        elif tmp6[0] == 'r' and tmp6 == ['r','e','s','a','r','e']:
            T += 'eraser'
            now += 6
        elif tmp7[0] == 'r' and tmp7 == ['r','e','m','a','e','r','d']:
            T += 'dreamer'
            now += 7
        else:
            print('NO')
            return

        if now >= len(S):
            break
    if Ss == T:
        print('YES')
    else:
        print('NO')

if __name__ == '__main__':
    main()


Fixed code:
def main():
    Ss = input()
    S = list(Ss)
    now = 0
    T = ''
    Sr = []
    for i in range(1,len(S)+1):
        Sr.append(S[-i])
    ans = []
    while True:
        tmp5 = Sr[now:now+5]
        tmp6 = Sr[now:now+6]
        tmp7 = Sr[now:now+7]
        if tmp5[0] == 'e' and tmp5 == ['e','s','a','r','e']:
            ans.append('erase')
            now += 5
        elif tmp5[0] == 'm' and tmp5 == ['m','a','e','r','d']:
            ans.append('dream')
            now += 5
        elif tmp6[0] == 'r' and tmp6 == ['r','e','s','a','r','e']:
            ans.append('eraser')
            now += 6
        elif tmp7[0] == 'r' and tmp7 == ['r','e','m','a','e','r','d']:
            ans.append('dreamer')
            now += 7
        else:
            print('NO')
            
            return

        if now >= len(S):
            break
    for i in range(1,len(ans)+1):
        T += ans[-i]
    if Ss == T:
        print('YES')
    else:
        print('NO')

if __name__ == '__main__':
    main()
Buggy code:
import numpy as np

d = np.array([[0, 0, 0, 0, 0, 0],
            [2, 0, 9, 0, 0, 0],
            [0, 3, 0, 0, 0, 0],
            [0, 0, 4, 0, 0, 0],
            [0, 0, 0, 5, 0, 0],
            [0, 0, 0, 0, 6, 0],
            [2, 0, 7, 0, 0, 0],
            [0, 8, 0, 0, 0, 0],
            [2, 0, 9, 11, 0, 0],
            [0, 10, 0, 0, 0, 0],
            [0, 0, 0, 11, 0, 0],
            [0, 0, 0, 0, 0, 12],
            [0, 0, 13, 0, 0, 0],
            [2, 1, 9, 0, 0, 0]], dtype = 'int32')
s = 1
for c in input():
    s = d[s][id[c]] if c in {'d': 0, 'r': 1, 'e': 2, 'a': 3, 'm': 4, 's': 5} else 0
    if s == 0:
        break
print("YES" if s in {1, 6, 8, 13} else "NO")


Fixed code:
import numpy as np

d = np.array([[0, 0, 0, 0, 0, 0],
            [2, 0, 9, 0, 0, 0],
            [0, 3, 0, 0, 0, 0],
            [0, 0, 4, 0, 0, 0],
            [0, 0, 0, 5, 0, 0],
            [0, 0, 0, 0, 6, 0],
            [2, 0, 7, 0, 0, 0],
            [0, 8, 0, 0, 0, 0],
            [2, 0, 9, 11, 0, 0],
            [0, 10, 0, 0, 0, 0],
            [0, 0, 0, 11, 0, 0],
            [0, 0, 0, 0, 0, 12],
            [0, 0, 13, 0, 0, 0],
            [2, 1, 9, 0, 0, 0]], dtype = 'int32')
s = 1
S = input()
N = len(S)
id = {'d': 0, 'r': 1, 'e': 2, 'a': 3, 'm': 4, 's': 5}
for c in S:
    s = d[s][id[c]] if c in id else 0
    if s == 0:
        break

print("YES" if s in {1, 6, 8, 13} else "NO")
Buggy code:
s = input().replace("eraser", "").replace("erace", "").replace("dreamer", "").replace("dream", "")
if len(s) > 0:
    print("NO")
else:
    print("YES")


Fixed code:
s = input().replace("eraser", "").replace("erase", "").replace("dreamer", "").replace("dream", "")
if len(s) > 0:
    print("NO")
else:
    print("YES")
Buggy code:
S = input()[::-1]
T = ["dream"[::-1],"dreamer"[::-1],"erase"[::-1],"eraser"[-1]]
Ans = "YES"
while len(S) > 0:
    if S[0:5] in T:
        S = S[5:]
        continue
    elif S[0:7] in T:
        S = S[7:]
        continue
    else:
        Ans = "NO"
        break
print(Ans)

Fixed code:
S = input()[::-1]
T = ["dream"[::-1],"dreamer"[::-1],"erase"[::-1],"eraser"[::-1]]
Ans = "YES"
while len(S) > 0:
    if S[0:5] in T:
        S = S[5:]
        continue
    elif S[0:6] in T:
        S = S[6:]
        continue
    elif S[0:7] in T:
        S = S[7:]
        continue
    else:
        Ans = "NO"
        break
print(Ans)
Buggy code:
def solve():

    S = input()

    words = ['dream', 'dreamer', 'erase', 'eraser']

    while(True):
        if(len(S) == 0):
            break
        flag = False
        for w in words:
            if(S.endswith(w)):
                S = S[0:len(S) - len(w)]
                flag = True
        
        if(not flag):
            return
            
        
    print('YES')
    
solve()

Fixed code:
def solve():

    S = input()

    words = ['dream', 'dreamer', 'erase', 'eraser']

    while(True):
        if(len(S) == 0):
            break
        flag = False
        for w in words:
            if(S.endswith(w)):
                S = S[0:len(S) - len(w)]
                flag = True
        
        if(not flag):
            print('NO')
            return
            
        
    print('YES')
    
solve()
Buggy code:
import sys

sys.setrecursionlimit(1000000)
S = input()


def start_with(i):
    if i == len(S)-1:
        print('YES')
        sys.exit(0)

    try:
        if S[i:i+5] == 'dream':
            start_with(i+5)
        if S[i:i+7] == 'dreamer':
            start_with(i+7)
        if S[i:i+5] == 'erase':
            start_with(i+5)
        if S[i:i+6] == 'eraser':
            start_with(i+6)
        return
    except IndexError:
        return


start_with(0)
print('NO')


Fixed code:
import sys

sys.setrecursionlimit(1000000)
S = input()


def start_with(i):
    if i == len(S):
        print('YES')
        sys.exit(0)

    try:
        if S[i:i+5] == 'dream':
            start_with(i+5)
        if S[i:i+7] == 'dreamer':
            start_with(i+7)
        if S[i:i+5] == 'erase':
            start_with(i+5)
        if S[i:i+6] == 'eraser':
            start_with(i+6)
        return
    except IndexError:
        return


start_with(0)
print('NO')
Buggy code:
# coding: utf-8
# Your code here!
S = input()
while True:
    if len(S)!=0:
        if S[len(S)-7:len(S)]=="dreamer":
            S = S.rstrip("dreamer")
        elif S[len(S)-6:len(S)]=="eraser":
            S = S.rstrip("eraser")
        elif S[len(S)-5:len(S)]=="dream":
            S = S.rstrip("dream")
        elif S[len(S)-5:len(S)]=="erase":
            S = S.rstrip("erase")
        else:
            print("NO")
            break
    else:
        print("YES")
        break


Fixed code:
# coding: utf-8
# Your code here!
S = input()
while True:
    if len(S)!=0:
        if S[len(S)-7:len(S)]=="dreamer":
            S = S[0:len(S)-7]
        elif S[len(S)-6:len(S)]=="eraser":
            S = S[0:len(S)-6]
        elif S[len(S)-5:len(S)]=="dream":
            S = S[0:len(S)-5]
        elif S[len(S)-5:len(S)]=="erase":
            S = S[0:len(S)-5]
        else:
            print("NO")
            break

    else:
        print("YES")
        break
Buggy code:
import re
print("YES" if re.match("^(dream|dreamer|erase|eraser)+$", input()) else 'No')

Fixed code:
import re
print("YES" if re.match("^(dream|dreamer|erase|eraser)+$", input()) else 'NO')
Buggy code:
S = input()
l = len(S)
while l > 0:
  if S[l-5:l] == 'erase' or S[l-5:l] == 'dream':
    l -= 5
  elif S[l-6:l] == 'eraser':
    l -= 6
  elif S[l-7:l] == 'dreamer':
    l -= 7
  else:
    l = -10
  print(l)
    
if l == 0:
  print("YES")
else:
  print("NO")

Fixed code:
S = input()
l = len(S)
while l > 0:
  if S[l-5:l] == 'erase' or S[l-5:l] == 'dream':
    l -= 5
  elif S[l-6:l] == 'eraser':
    l -= 6
  elif S[l-7:l] == 'dreamer':
    l -= 7
  else:
    l = -10
    
if l == 0:
  print("YES")
else:
  print("NO")
Buggy code:
s = str(input())

T = ["dream", "dreamer", "erase", "eraser"]

new_s =reversed(s)
new_t = []
for item in T:
  new_t.append(reversed(item))

ans_t =''
  
for c in new_s:
  collector += c
  if collector in new_t:
    ans_t += collector
    collector = ''
    
if new_s == ans_t:
  print('YES')
else:
  print('NO')

Fixed code:
s = str(input())

T = ["dream", "dreamer", "erase", "eraser"]

new_s =s[::-1]
new_t = []
for item in T:
  new_t.append(item[::-1])

ans_t =''
collector = ''

for c in new_s:
  collector += c
  if collector in new_t:
    ans_t += collector
    collector = ''
    
if new_s == ans_t:
  print('YES')
else:
  print('NO')
Buggy code:
import re
s = input()
re.sub('eraser','0',s)
re.sub('erase','0',s)
re.sub('dreamer','0',s)
re.sub('dream','0',s)


print('YES' if set(s) == set('0') else 'NO')

Fixed code:
import re
s = input()
s = re.sub('eraser','0',s)
#print(s)
s = re.sub('erase','0',s)
#print(s)
s = re.sub('dreamer','0',s)
#print(s)
s = re.sub('dream','0',s)
#print(s)


print('YES' if set(s) == set('0') else 'NO')
Buggy code:
s = input()
dp = [0]*(len(s) + 1)
dp[0] = 1
judge = 'NO'
word = ['dream', 'dreamer', 'erase', 'eraser']
for i in range(len(s)):
  if d[i] = 0:
    continue
  for w in words():
    if s[i:i+len(w)] == w:
      dp[i+len(w)] = 1
    if dp[len(s)] == 1:
      judge = 'YES'
      break
print(judge)

Fixed code:
s = input()
dp = [0]*(len(s) + 1)
dp[0] = 1
judge = 'NO'
words = ['dream', 'dreamer', 'erase', 'eraser']
for i in range(len(s)):
  if dp[i] == 0:
    continue
  for w in words:
    if s[i:i+len(w)] == w:
      dp[i+len(w)] = 1
    if dp[len(s)] == 1:
      judge = 'YES'
      break
print(judge)
Buggy code:
S = input()
if len(S) == 0:
  print('NO')
if len(S.replace('dreamer', '').replace('dream', '').replace('eraser', '').replace('erase', '')) == 0:
  print('YES')
else:
  print('NO')

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

while True:
  if s == "":
    print('YES')
    break
  elif s[-5:] == 'dream' or s[-5:] == 'erase':
    s = s[:-5]
  elif s[-6:] == 'erase':
    s = s[:-6]
  elif s[-7:] == 'dreamer':
    s = s[:-7]
  else:
    print('NO')
    break
      
  

Fixed code:
s = input()

while True:
  if s == "":
    print('YES')
    break
  elif 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:
    print('NO')
    break
Buggy code:
S = input()

result = "NO"

while True:
    if S[-5:-1] == "dream":
        if len(S) == 5:
            result = "YES"
            break
        S.rstrip("dream")
    elif S[-5:-1] == "erase":
        if len(S) == 5:
            result = "YES"
            break
        S.rstrip("erase")
    elif S[-6:-1] == "eraser":
        if len(S) == 6:
            result = "YES"
            break
        S.rstrip("eraser")
    elif S[-7:-1] == "dreamer":
        if len(S) == 7:
            result = "YES"
            break
        S.rstrip("dreamer")
    else:
        break

print(result)

Fixed code:
S = input()

result = "NO"

while True:
    if S[-5:] == "dream":
        if len(S) == 5:
            result = "YES"
            break
        S = S[:-5]
    elif S[-5:] == "erase":
        if len(S) == 5:
            result = "YES"
            break
        S = S[:-5]
    elif S[-6:] == "eraser":
        if len(S) == 6:
            result = "YES"
            break
        S = S[:-6]
    elif S[-7:] == "dreamer":
        if len(S) == 7:
            result = "YES"
            break
        S = S[:-7]
    else:
        break

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

Fixed code:
s = input()
s = s.replace('eraser', '')
s = s.replace('erase', '')
s = s.replace('dreamer', '')
s = s.replace('dream', '')
print('YES' if len(s)==0 else 'NO')
Buggy code:
S = input()
Sr = S[::-1]
token = ['dream', 'dreamer', 'erase', 'eraser']
tokenr = list(map(lambda x:x[::-1], token))
t = ''
while(len(Sr)>0):
    notFound = True
    for w in tokenr:
        if w==Sr[:len(w)]:
            Sr = Sr[len(w):]
            t+=w
            notFound = False
    if notFound:
        break
if Sr == '':
    print('Yes')
else:
    print('No')

Fixed code:
S = input()
Sr = S[::-1]
token = ['dream', 'dreamer', 'erase', 'eraser']
tokenr = list(map(lambda x:x[::-1], token))
t = ''
while(len(Sr)>0):
    notFound = True
    for w in tokenr:
        if w==Sr[:len(w)]:
            Sr = Sr[len(w):]
            t+=w
            notFound = False
    if notFound:
        break
if Sr == '':
    print('YES')
else:
    print('NO')
Buggy code:
S=input()
S=S.split("dream")
S="".join(S)
S=S.split("dreamer")
S="".join(S)
S=S.split("erase")
S="".join(S)
S=S.split("eraser")
S="".join(S)
print("YES") if S=="" else print("NO")

Fixed code:
S=input()
S=S.split("eraser")
S="".join(S)
S=S.split("erase")
S="".join(S)
S=S.split("dreamer")
S="".join(S)
S=S.split("dream")
S="".join(S)
print("YES") if S=="" else print("NO")
Buggy code:
a=("dream","erase");ans="YES"
s=input()
while s!="":
  if s[:7]=="dreamer":s=s[7:]
  elif s[:6]=="eraser":s=s[6:]
  elif s[:5]in a:s=s[5:]
  else:ans="NO";break
print(ans)

Fixed code:
a=("dream","erase");ans="YES"
s=input()
while s!="":
  if s[-7:]=="dreamer":s=s[:-7]
  elif s[-6:]=="eraser":s=s[:-6]
  elif s[-5:]in a:s=s[:-5]
  else:ans="NO";break
print(ans)
Buggy code:
s = input()
 
ans = 'YES'
 
while len(s) > 0:
    if s.endswith('dreamer'):
        s = s[:-7]
    elif s.endswith('dream'):
        s = s[:-5]
    elif s.endswith('eraser'):
        s = s[:-6]
    elif s.endswith('erase'):
        s = s[:-5]
    else:
        ans = 'NO'

Fixed code:
s = input()
 
ans = 'YES'
 
while len(s) > 0:
    if s.endswith('dreamer'):
        s = s[:-7]
    elif s.endswith('dream'):
        s = s[:-5]
    elif s.endswith('eraser'):
        s = s[:-6]
    elif s.endswith('erase'):
        s = s[:-5]
    else:
        ans = 'NO'
        break
 
print(ans)
Buggy code:
s = input()
str = s.replace('dreamer','').replace('dream','').replace('eraser','').replace('erase', '')
if len(str) == 0:
    print('YES')
else:
    print('NO')


Fixed code:
s = input()
str = s.replace('eraser','').replace('erase','').replace('dreamer','').replace('dream', '')
if len(str) == 0:
    print('YES')
else:
    print('NO')
Buggy code:
# -*- coding:utf-8 -*-

s = input().replace("dreamer","").replace("dream","")\
        .replace("eraser","").replace("erase","")
if s:
        print("NO")
else:
        print("YES")

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

s = input().replace("eraser","").replace("erase","")\
        .replace("dreamer","").replace("dream","")
if s:
        print("NO")
else:
        print("YES")
Buggy code:
S=input()
S=S[::-1]
divide=['dream','dreamer','erase','eraser'] 
flag=False
for i in range(4):
  divide[i]=divide[i][::-1]

i=0
while i<(len(S)-1):
  flag=False
  for d in divide:
    if i+(len(d)-1):   
      flag=True
      i+=len(d)-1
      break

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

Fixed code:
S=input()
S=S[::-1]
divide=['dream','dreamer','erase','eraser'] 
flag=False
for i in range(4):
  divide[i]=divide[i][::-1]

i=0
while i!=len(S):
  flag=False
  for d in divide:
    if S[i:i+len(d)]==d:   
      flag=True
      i+=len(d)
      break
    
  if flag==False:
     break
      
print('YES' if flag else 'NO')
Buggy code:
s = input()
str_list = ["eraser","erase","dreamer","dream"]
for e in str_list:
    s = s.replace(e)
ans = "YES" if s == "" else "NO"
print(ans)

Fixed code:
s = input()
str_list = ["eraser","erase","dreamer","dream"]
for e in str_list:
    s = s.replace(e,"")
ans = "YES" if s == "" else "NO"
print(ans)
Buggy code:
s = input()
str_list = ["dream","dreamer","erase","eraser"]
for i in range(len(s) // 5):
    if s[-5:] == "dream" or s[-5:] == "erase":
        s = s[:-5]
    elif s[-6:] == "eraser":
        s = s[:-6]
    elif s[-7:] == "dreamer":
        s = s[:-7]
ans = "YES" if s == "" else "No"
print(ans) 

Fixed code:
s = input()
str_list = ["dream","dreamer","erase","eraser"]
for i in range(len(s) // 5):
    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]
ans = "YES" if s == "" else "NO"
print(ans)
Buggy code:
s = input().replace("dreamer","")
s = s.replace("eraser","")
s = s.replace("dream","")
s = s.replace("erase","")

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

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

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

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

S = S.replace("dream",'/*/').replace('erase','/+/')
S = S.split('/')
while '' in S:
    S.remove('')
print(S)
for i in range(len(S)):
    if S[i] == '*' or S[i] == '+':
        continue
    if S[i] == 'r':
        if i != 0 and S[i-1] == '+':
            continue
    elif S[i] == 'er':
        if i != 0 and S[i-1] == '*':
            continue
    print('NO')
    exit()
print('YES')
            

Fixed code:
S = input()

S = S.replace("dream",'/*/').replace('erase','/+/')
S = [i for i in S.split('/') if i != '']
for i in range(len(S)):
    if S[i] == '*' or S[i] == '+':
        continue
    if S[i] == 'r':
        if i != 0 and S[i-1] == '+':
            continue
    elif S[i] == 'er':
        if i != 0 and S[i-1] == '*':
            continue
    print('NO')
    exit()
print('YES')
Buggy code:
s = input()

flag = 0
while(1):
  if len(s) == 0:
    flag = 1
    break
  elif s[0:5] == "dream":
    s = s[5:]
  elif s[0:5] == "erase":
    s = s[5:]
  elif s[0:6] == "eraser":
    s = s[6:]
  elif s[0:7] == "dreamer":
    s = s[7:]
  else:
    break

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

Fixed code:
s = input()

flag = 0
while(1):
  if len(s) == 0:
    flag = 1
    break
  elif s[-7:] == "dreamer":
    s = s[0:-7]
  elif s[-6:] == "eraser":
    s = s[0:-6]
  elif s[-5:] == "dream":
    s = s[0:-5]
  elif s[-5:] == "erase":
    s = s[0:-5]
  else:
    break

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

while len(S) > 0:
  if "dreameraser" in S:
    S = S.replace("dreameraser","")
  elif "dream" in S:
    S = S.replace("dreamer","")
  elif "dreamer" in S:
    S = S.replace("dream","")
  elif "erase" in S:
    S = S.replace("eraser","")
  elif "eraser" in S:
    S = S.replace("erase","")
  else:
    break
    
if len(S) == 0:
  print("YES")
else:
  print("NO")

Fixed code:
S = input()
 
while len(S) > 0:
  if "dreameraser" in S:
    S = S.replace("dreameraser","")
  elif "dreamerase" in S:
    S = S.replace("dreamerase","")
  elif "dreamer" in S:
    S = S.replace("dreamer","")
  elif "dream" in S:
    S = S.replace("dream","")
  elif "eraser" in S:
    S = S.replace("eraser","")
  elif "erase" in S:
    S = S.replace("erase","")
  else:
    break
    
if len(S) == 0:
  print("YES")
else:
  print("NO")
Buggy code:
S = input()
C = ["maerd","remaerd","esare","resare"]
ans = ""
a = "YES"
x = len(S)
for i in range(x):
    ans = ans + S[x - 1 -i]
    if ans == C[0]:
        ans = ""
    elif ans == C[1]:
        ans = ""
    elif ans == C[2]:
        ans = ""
    elif ans == C[3]:
        ans = ""
if len(ans) != 0:
    a = "No"
print(a)


Fixed code:
S = input()
C = ["maerd","remaerd","esare","resare"]
ans = ""
a = "YES"
x = len(S)
for i in range(x):
    ans = ans + S[x - 1 -i]
    if ans == C[0]:
        ans = ""
    elif ans == C[1]:
        ans = ""
    elif ans == C[2]:
        ans = ""
    elif ans == C[3]:
        ans = ""
if len(ans) != 0:
    a = "NO"
print(a)