qyliang/CodeNanoFix huggingface dataset:
Buggy code:
S = input()

def solve(T) :
    while 1:
        flag = True
        for i in ("dream", "dreamer", "erase", "eraser"):
            if T.endswith(i):
                T = T[: -len(i)]
                flag = False
                break
        
        if flag:
            print("NO")
            break
        
        if len(T) == 0:
            print("Yes")
            break

solve(S)

Fixed code:
S = input()

def solve(T) :
    while 1:
        flag = True
        for i in ("dream", "dreamer", "erase", "eraser"):
            if T.endswith(i):
                T = T[: -len(i)]
                flag = False
                break
        
        if flag:
            print("NO")
            break
        
        if len(T) == 0:
            print("YES")
            break

solve(S)
Buggy code:
S = input()

def solve(T) :
    while 1:
        for i in ("dream", "dreamer", "erase", "eraser"):
            if T.endswith(i):
                T = T[: -len(i)]
                break
        
        else:
            print("NO")
            break
        
        if not T:
            print("Yes")
            break

solve(S)

Fixed code:
S = input()

def solve(T) :
    while 1:
        for i in ("dream", "dreamer", "erase", "eraser"):
            if T.endswith(i):
                T = T[: -len(i)]
                break
        
        else:
            print("NO")
            break
        
        if not T:
            print("YES")
            break

solve(S)
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:
def extract_6(x):
	strtemp=' '
	if(len(x)>=6):
		temp=[0]*6
		for i in range(6):
			temp[i]=x[len(x)-6+i]
	else:
		temp='false'
	strtemp=''.join(temp)
	print(strtemp)
	return(strtemp)

def extract_5(x):
	strtemp=' '
	if(len(x)>=5):
		temp=[0]*5
		for i in range(5):
			temp[i]=x[len(x)-5+i]
	else:
		temp='false'
	strtemp=''.join(temp)
	print(strtemp)
	return(strtemp)

S=input()
flag=1
while(flag==1):
	if(extract_6(S)=='dreamer'):
		S=S.rstrip('dreamer')
	elif(extract_6(S)=='eraser'):
		S=S.rstrip('eraser')
	elif(extract_5(S)=='dream'):
		S=S.rstrip('dream')
	elif(extract_5(S)=='erase'):
		S=S.rstrip('erase')
	else:
		flag=0
if len(S)!=0:
	print('NO')
else:
	print('YES')
print(S)

Fixed code:
def extract_6(x):
	strtemp=' '
	if(len(x)>=6):
		temp=[0]*6
		for i in range(6):
			temp[i]=x[len(x)-6+i]
	else:
		temp='false'
	strtemp=''.join(temp)
	return(strtemp)

def extract_5(x):
	strtemp=' '
	if(len(x)>=5):
		temp=[0]*5
		for i in range(5):
			temp[i]=x[len(x)-5+i]
	else:
		temp='false'
	strtemp=''.join(temp)
	return(strtemp)
	
def extract_7(x):
	strtemp=' '
	if(len(x)>=7):
		temp=[0]*7
		for i in range(7):
			temp[i]=x[len(x)-7+i]
	else:
		temp='false'
	strtemp=''.join(temp)
	return(strtemp)

S=input()
flag=1
while(flag==1):
	if(extract_7(S)=='dreamer'):
		S=S[:-7]
	elif(extract_6(S)=='eraser'):
		S=S[:-6]
	elif(extract_5(S)=='dream'):
		S=S[:-5]
	elif(extract_5(S)=='erase'):
		S=S[:-5]
	else:
		flag=0
if len(S)!=0:
	print('NO')
else:
	print('YES')
Buggy code:
s=input().strip()
s=s.replace("eraser","")
s=s.replace("erase","")
s=s.replace("dreamer","")
s=s.replace("dream","")
print("YES" if s else "NO")

Fixed code:
s=input().strip()
s=s.replace("eraser","")
s=s.replace("erase","")
s=s.replace("dreamer","")
s=s.replace("dream","")
print("YES" if not s else "NO")
Buggy code:
import sys
s = input()
A = ['dream','dreamer','erase', 'eraser']
while(len(s)!=0):
    cs = s
    for i in range(len(A)):
        if (s.startswith(str(A[i]))):
            #print(A[len(A[i])+1:])
            s = s[len(A[i]):]
    if (cs == s):
        print('NO')
        sys.exit()
print('YES')

Fixed code:
import sys
s = input()
s = s[::-1]
A = ['dreamer','dream','eraser', 'erase']
for i in range(len(A)):
    A[i] = A[i][::-1]
while(len(s)!=0):
    cs = s
    for i in range(len(A)):
        if (s.startswith(str(A[i]))):
            #print(A[len(A[i])+1:])
            s = s[len(A[i]):]
            #print(s)
            break
    if (cs == s):
        print('NO')
        sys.exit()
print('YES')
Buggy code:
s = input()
if s.replace("eraser","　").replace("erase","　").replace("dreamer","　").replace("dream","　").replace(" ", ""):
    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()
word_list =['dream', 'dreamer', 'erase', 'eraser']

S = S[::-1]
word_list = [i[::-1]for i in word_list]

for i in word_list:
        S = S.replace(i, '')

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

Fixed code:
S = input()
word_list =['eraser', 'erase', 'dreamer', 'dream']

for i in word_list:
        S = S.replace(i, '')
if S == '':
    print('YES')
else:
    print('NO')
Buggy code:
a=input()
a=a.replace("erase","")
a=a.replace("dream","")
a=a.replace("dreamer","")
a=a.replace("eraser","")
if a="":
  print("YES")
else:
  print("NO")

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

a=a.replace("dream","")
if a=="":
  print("YES")
else:
  print("NO")
Buggy code:

s = input()

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


if len(s) == 0:
    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:
s = input()
a = 0
t = ("")

while a < len(s):
    if s[a+0:a+5] == ("dream") and s[a+0+2:a+5+2] != ("er"):
        a += 5
        t += ("dream")

    elif s[a+0:a+5] == ("dream") and s[a+0+2:a+5+2] == ("er"):
        if s[a+7+0:a+7+3] != ("ase"):
            a += 7
            t += ("dreamer")

        elif s[a+7+0:a+7+3] == ("ase") and s[a+10+0:a+10+1] != ("r"):
            a += 10
            t += ("dreamerase")

        elif s[a+7+0:a+7+3] == ("ase") and s[a+10+0:a+10+1] == ("r"):
            a += 11
            t += ("dreameraser")

    elif s[a+0:a+5] == ("erase") and s[a+5+0:a+5+1] != ("r"):
        a += 5
        t += ("erase")

    elif s[a+0:a+5] == ("erase") and s[a+5+0:a+5+1] == ("r"):
        a += 6
        t += ("eraser")

    else:
        break

print(t)

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


Fixed code:
s = input()
a = 0
t = ("")

while a < len(s):
    if s[a+0:a+5] == ("dream") and s[a+5+0:a+5+2] != ("er"):
        a += 5

    elif s[a+0:a+5] == ("dream") and s[a+5+0:a+5+2] == ("er"):
        if s[a+7+0:a+7+3] != ("ase"):
            a += 7

        elif s[a+7+0:a+7+3] == ("ase") and s[a+10+0:a+10+1] != ("r"):
            a += 10

        elif s[a+7+0:a+7+3] == ("ase") and s[a+10+0:a+10+1] == ("r"):
            a += 11

    elif s[a+0:a+5] == ("erase") and s[a+5+0:a+5+1] != ("r"):
        a += 5

    elif s[a+0:a+5] == ("erase") and s[a+5+0:a+5+1] == ("r"):
        a += 6

    else:
        break

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

Fixed code:
print('YES'if input().replace('eraser','').replace('erase','').replace('dreamer','').replace('dream','')==''else'NO')
Buggy code:
s=input()
s.replace("eraser","").replace("erase","").replace("dreamer","").replace("dream","")
if len(s)==0:
    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:
a = input()
num = len(a)
ans = ''
while num>0:
    if a[num-1] == 'm':
        ans = 'dream' + ans
        num -= 5
    elif a[num-1] == 'e':
        ans = 'erase' + ans
        num -=5
    elif a[num-3:num] == 'mer':
        ans = 'dreamer'+ans
        num -=7
    elif a[num-3:num] == 'ser':
        ans = 'eraser'+ans
        num -= 7
    else:
        break
if ans == a:
    print('YES')
else:
    print('NO')

Fixed code:
a = input()
num = len(a)
ans = ''
while num>0:
    if a[num-1] == 'm':
        ans = 'dream' + ans
        num -= 5
    elif a[num-1] == 'e':
        ans = 'erase' + ans
        num -=5
    elif a[num-3:num] == 'mer':
        ans = 'dreamer'+ans
        num -=7
    elif a[num-3:num] == 'ser':
        ans = 'eraser'+ans
        num -= 6
    else:
        break
if ans == a:
    print('YES')
else:
    print('NO')
Buggy code:
S = input()
words = ['dreamer', 'dream', 'eraser', 'erase']
for w in words:
    S = S.replace(w,"")
print("YES" if len(S) == 0 else "NO")

Fixed code:
S = input()
words = ['eraser', 'erase', 'dreamer', 'dream']
for w in words:
    S = S.replace(w,"")
print("YES" if len(S) == 0 else "NO")
Buggy code:
S = input()
case =True
while(case == True):
    if len(S) <5:
        case = False
    
    elif S[0:5] == 'dream': #check 'dreamer' and 'dream'
        if len(S) > 6 and S[5] == 'e' and S[6] == 'r':
            S = S[7:]
        else:
            S = S[5:]

    elif S[0:5] == 'erase': #check 'erase' and 'eraser'
        if len(S) > 5 and S[5] == 'r':
            S = S[6:]
        else:
            S = S[5:]
    
    else:
        case =False

if len(S) == 0:
    print('YES')
else:
    print('NO')
#print(S)

Fixed code:
S = input()
case =True
while(case == True):
    if len(S) <5:
        case = False
    
    elif S[0:5] == 'dream': #check 'dreamer' and 'dream'
        if S[0:10] == 'dreamerase':
            S = S[5:]
        elif S[0:7] == 'dreamer':
            S = S[7:]
        else:
            S = S[5:]

    elif S[0:5] == 'erase': #check 'erase' and 'eraser'
        if len(S) > 5 and S[5] == 'r':
            S = S[6:]
        else:
            S = S[5:]
    
    else:
        case =False

if len(S) == 0:
    print('YES')
else:
    print('NO')
#print(S)
Buggy code:
S = input()
l = ['dreamer', 'dream', 'eraser','erase']

s = "".join(S.split(l[0]))

for i in range(1, 4):
    s = "".join(s.split(l[i]))

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


Fixed code:
S = input()
l = ['eraser', 'erase', 'dreamer','dream']

s = "".join(S[-1::-1].split(l[0][-1::-1]))

for i in range(1, 4):
    s = "".join(s.split(l[i][-1::-1]))

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

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

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

if s == "":
    print("YES")
else:
    print("NO")
Buggy code:
import sys
s = list(input())
check =['dream','dreamer','erase','eraser']
while len(s) >= 8:
    if ''.join(s[-5:]) == check[0]:
        print(s)
        for _ in range(5): s.pop()
        continue
    if ''.join(s[-7:]) == check[1]:
        print(s)
        for _ in range(7): s.pop()
        continue
    if ''.join(s[-5:]) == check[2]:
        print(s)
        for _ in range(5): s.pop()
        continue
    if ''.join(s[-6:]) == check[3]:
        print(s)
        for _ in range(6): s.pop()
        continue
    print('No')
    sys.exit()
if ''.join(s) == check[0] or ''.join(s) == check[1] or ''.join(s) == check[2] or ''.join(s) == check[3]:
    print('Yes')
else:
    print('No')


Fixed code:
import sys
s = list(input())
check =['dream','dreamer','erase','eraser']
while len(s) >= 8:
    if ''.join(s[-5:]) == check[0]:
        for _ in range(5): s.pop()
        continue
    if ''.join(s[-7:]) == check[1]:
        for _ in range(7): s.pop()
        continue
    if ''.join(s[-5:]) == check[2]:
        for _ in range(5): s.pop()
        continue
    if ''.join(s[-6:]) == check[3]:
        for _ in range(6): s.pop()
        continue
    print('NO')
    sys.exit()
if ''.join(s) == check[0] or ''.join(s) == check[1] or ''.join(s) == check[2] or ''.join(s) == check[3]:
    print('YES')
else:
    print('NO')
Buggy code:
def main():
    target = input()
    string = ["eraser", "dreamer", "erase", "dream"]
    for i in range(len(target)):
        for s in string:
            if target[i - len(s):] == s:
                target = target[:i - len(s)]
                break
        print(target)
    print("YES" if target == "" else "NO")


if __name__ == '__main__':
    main()



Fixed code:
def main():
    target = input()
    string = ["eraser", "dreamer", "erase", "dream"]
    for i in range(len(target)):
        for s in string:
            if target[-len(s):] == s:
                target = target[:-len(s)]
        if target == "":
            break
    print("YES" if target == "" else "NO")


if __name__ == '__main__':
    main()
Buggy code:
S = input()
S = list(S)
s = ''.join(list(reversed(S)))
def main(s):
  l = ["esare", "maerd", "resare", "remaerd"]
  for i in l:
    s = s.replace(i, '')
  return s
if main(s) == '':
  print('YES')
elif main(s) != '':
  print('NO')

Fixed code:
S = input()
S = list(S)
s = ''.join(list(reversed(S)))
def main(s):
  l = ["resare", "esare","remaerd", "maerd"]
  for i in l:
    s = s.replace(i, '')
  return s
if main(s) == '':
  print('YES')
elif main(s) != '':
  print('NO')
Buggy code:
S = input()
S = S[::-1]

divide = ["dream", "dreamer", "erase", "eraser"]
for i in range(4):
    divide[i] = divide[i][::-1]

length1 = 0
length2 = 0
can = 0
flag = True

while flag:
    length1 = length2
    for i in range(4):
        if S[length1:length1+len(divide[i])] == divide[i]:
            length2 = length1 + len(divide[i])
    if length1 == length2:
        flag = False

if len(S) == length2:
    print("YES")
else:
    print("NO")

print(length2)

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

divide = ["dream", "dreamer", "erase", "eraser"]
for i in range(4):
    divide[i] = divide[i][::-1]

length1 = 0
length2 = 0
can = 0
flag = True

while flag:
    length1 = length2
    for i in range(4):
        if S[length1:length1+len(divide[i])] == divide[i]:
            length2 = length1 + len(divide[i])
    if length1 == length2:
        flag = False

if len(S) == length2:
    print("YES")
else:
    print("NO")
Buggy code:
import sys

S = input()

while True:
    if S == '':
        print('YES')
        sys.exit(0)
    if len(S) < 5:
        print('NO')
        sys.exit(0)
    third = S[-3]
    if third == 'e':
        if len(S) < 5 or S[-5:] != 'dream':
            print('NO')
            sys.exit(0)
        S = S[:-5]
    if third == 'a':
        if len(S) < 5 or S[-5:] != 'erase':
            print('NO')
            sys.exit(0)
        S = S[:-5]
    if third == 'm':
        if len(S) < 7 or S[-7:] != 'dreamer':
            print('NO')
            sys.exit(0)
        S = S[:-7]
    if third == 's':
        if len(S) < 6 or S[-6:] != 'eraser':
            print('NO')
            sys.exit(0)
        S = S[:-6]


Fixed code:
import sys

S = input()

while len(S) > 0:
    if len(S) < 5:
        print('NO')
        sys.exit(0)
    third = S[-3]
    if third == 'e':
        if len(S) < 5 or S[-5:] != 'dream':
            print('NO')
            sys.exit(0)
        S = S[:-5]
        continue
    if third == 'a':
        if len(S) < 5 or S[-5:] != 'erase':
            print('NO')
            sys.exit(0)
        S = S[:-5]
        continue
    if third == 'm':
        if len(S) < 7 or S[-7:] != 'dreamer':
            print('NO')
            sys.exit(0)
        S = S[:-7]
        continue
    if third == 's':
        if len(S) < 6 or S[-6:] != 'eraser':
            print('NO')
            sys.exit(0)
        S = S[:-6]
        continue
    else:
        print('NO')
        sys.exit(0)

print('YES')
Buggy code:
dr ="dream" 
dre = "dreamer" 
er ="erase" 
ere = "eraser" 
a = input()
ret = "YES"
while len(a) != 0:
    if (a.endswith(dr) or a.endswith(er)):
        a = a[:len(a)-5]
    elif(a.endswith(dre) or a.endswith(ere)):
        a = a[:len(a)-7]
    else:
        ret = "NO"
        break
        
print(ret)

Fixed code:
dr ="dream" 
dre = "dreamer" 
er ="erase" 
ere = "eraser" 
a = input()
ret = "YES"
while len(a) != 0:
    if (a.endswith(dr) or a.endswith(er)):
        a = a[:len(a)-5]
    elif(a.endswith(dre)):
        a = a[:len(a)-7]
    elif(a.endswith(ere)):
        a = a[:len(a)-6]
    else:
        ret = "NO"
        break
        
print(ret)
Buggy code:
s = input()
t = ''
while s:
    a = ''
    for i in ['dream', 'erase', 'eraser', 'dreamer']:
        if s.startswith(i) : a = i; break
    if a == '' : print('NO');exit()
    s = s[len(a):]
print('YES')

Fixed code:
s = input()
t = ''
while s:
    a = ''
    for i in ['eraser', 'erase', 'dreamer', 'dream']:
        if s.endswith(i) : a = i; break
    if a == '' : print('NO');exit()
    s = s[:-len(a)]
print('YES')
Buggy code:
s = input()

while s == "":
	is_match = False
	for word in ("dream", "dreamer", "erase", "eraser"):
		if s[-len(word):] == word:
			s = s[:-len(word)]
			is_match = True
	if is_match == False:
		print("NO")
		exit()
print("YES")

Fixed code:
s = input()

while s != "":
	is_match = False
	for word in ("dream", "dreamer", "erase", "eraser"):
		if s[-len(word):] == word:
			s = s[:-len(word)]
			is_match = True
	if is_match == False:
		print("NO")
		exit()
print("YES")
Buggy code:
words = ("dream", "erase", "eraser", "dreamer")

s = input()

while len(s) > 0:
    match = False
    for w in words:
        if s.endwith(w):
            s = s[:-len(w)]
            match = True
            break
    if match is False:
        print("NO")
        exit()
print("YES")


Fixed code:
words = ("dream", "erase", "eraser", "dreamer")

s = input()

while len(s) > 0:
    match = False
    for w in words:
        if s.endswith(w):
            s = s[:-len(w)]
            match = True
            break
    if match is False:
        print("NO")
        exit()
print("YES")
Buggy code:
S = input()
N = ['dream', 'dreamer', 'erase', 'eraser']

S = S[::-1]

t = []
i = 0
T = ''

if len(S) < 3:
    print('No')
else:
    while i<len(S):
        if S[i] == 'm' and S[i+1] == 'a' and S[i+2] == 'e':
            letter = 'dream'
            i += 4
        elif S[i] ==  'r' and S[i+1] == 'e' and S[i+2] == 'm':
            letter = 'dreamer'
            i += 6
        elif S[i] == 'e' and S[i+1] == 's' and S[i+2] == 'a':
            letter = 'erase'
            i += 4
        elif S[i] == 'r' and S[i+1] == 'e' and S[i+2] == 's':
            letter = 'eraser'
            i += 6
        else:
            break
        i += 1
        t.append(letter)

#print(t)

    for x in t[::-1]:
        T += x

#print(T)

    if S == T[::-1]:
        print('YES')
    else:
        print('NO')


Fixed code:
S = input()
N = ['dream', 'dreamer', 'erase', 'eraser']

S = S[::-1]

t = []
i = 0
T = ''

if len(S) < 3:
    print('No')
else:
    while i<len(S):
        if S[i] == 'm' and S[i+1] == 'a' and S[i+2] == 'e':
            letter = 'dream'
            i += 4
        elif S[i] ==  'r' and S[i+1] == 'e' and S[i+2] == 'm':
            letter = 'dreamer'
            i += 6
        elif S[i] == 'e' and S[i+1] == 's' and S[i+2] == 'a':
            letter = 'erase'
            i += 4
        elif S[i] == 'r' and S[i+1] == 'e' and S[i+2] == 's':
            letter = 'eraser'
            i += 5
        else:
            break
        i += 1
        t.append(letter)

#print(t)

    for x in t[::-1]:
        T += x

#print(T)

    if S == T[::-1]:
        print('YES')
    else:
        print('NO')
Buggy code:
S = str(input())

while len(S) > 0:
  if S[-5:] == 'dream' or S[-5:] == 'erase':
    S = S[:-5]
  elif S[-7:] == 'dreamer' or S[-7:] == 'eraser':
    S = S[:-7]
  else:
    break

if len(S) == 0:
  print('YES')
else:
  print('NO')

Fixed code:
S = str(input())

while len(S) > 0:
  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]
  else:
    break

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

Fixed code:
S = input()
S = S.replace("eraser","")
S = S.replace("erase","")
S = S.replace("dreamer","")
S = S.replace("dream","")
if S == "":
  print("YES")
else:
  print("NO")
Buggy code:
S = list(input())
while len(S) > 0:
    print(S)
    if ''.join(S[-5:]) == 'dream' or ''.join(S[-5:]) == 'erase':
        S = S[:-5]
    elif ''.join(S[-6:]) == 'eraser':
        S = S[:-6]
    elif ''.join(S[-7:]) == 'dreamer':
        S = S[-7:]
    else:
        print('NO')
        quit()
print('YES')

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

a = s.count("dream")
b = s.count("dreamer")
c = s.count("erase")
d = s.count("eraser")
if a*5 + b*7 + c*5 + d*6 == len(s):
  print("YES")
else:
  print("NO")

Fixed code:
s = input()
 
x = s.count("dreamerase")
a = s.count("dreamer") - x
b = s.count("dream") - a 
c = s.count("eraser")
d = s.count("erase") - c

if a*7 + b*5 + c*6 + d*5 == len(s):
  print("YES")
else:
  print("NO")
Buggy code:
import re
s = (re.sub("dreamer|eraser|erase|dream", "", str(input())))
print("YES") if  s == "" else print("NO")

Fixed code:
import re
s = (re.sub("eraser|erase", "", str(input())))
s = (re.sub("dreamer|dream", "", s))
print("YES") if  s == "" else print("NO")
Buggy code:
s=input()
s.replace("eraser","").replace("erase","").replace("dreamer","").replace("dream","")
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()[::-1]
while len(s) > 0 :
    if s[:7] == 'remaerd':
        s = s[7:]
    elif s[:7] == 'resare':
        s = s[7:]
    elif s[:5] == 'maerd':
        s = s[5:]
    elif s[:5] == 'esare':
        s = s[5:]
    else:
        break
print(('NO','Yes')[len(s)==0])

Fixed code:
s = input()[::-1]
while len(s) > 0 :
    if s[:7] == 'remaerd':
        s = s[7:]
    elif s[:6] == 'resare':
        s = s[6:]
    elif s[:5] == 'maerd':
        s = s[5:]
    elif s[:5] == 'esare':
        s = s[5:]
    else:
        break
print(('NO','YES')[len(s)==0])
Buggy code:
div = ["dream", "dreamer", "erase", "eraser"]
rev = []
t = ""
s_rev = s[::-1]
for d in div:
    rev.append(d[::-1])

result = True
i = 0
while i < len(s):
    print(i)
    can_divide = False
    for d in rev:
        if s_rev[i:i + len(d)] == d:
            can_divide = True
            i += len(d)
    if not can_divide:
        result = False
        break

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

Fixed code:
s = input()
div = ["dream", "dreamer", "erase", "eraser"]
rev = []
t = ""
s_rev = s[::-1]
for d in div:
    rev.append(d[::-1])

result = True
i = 0
while i < len(s):
    can_divide = False
    for d in rev:
        if len(s_rev) - i >= len(d) and s_rev[i:i + len(d)] == d:
            can_divide = True
            i += len(d)
            break
    if not can_divide:
        result = False
        break

print("YES" if result else "NO")
Buggy code:
s = input()
q = [0]
flag = False
while len(s) > 0:
    if s[0:5] in ['dream','erase'] and flag == False:
        q.append(s[0:5])
        s = s[5:]
        flag = False
    elif s[0:6] == 'eraser':
        q.append(s[0:6])
        s = s[6:]
        flag = False
    elif s[0:7] == 'dreamer':
        q.append(s[0:7])
        s = s[7:]
        flag = False
    elif q[-1] in ['dream','erase']:
        s = q[-1] + s
        q.pop()
        flag = True
    else:
        print('NO')
        exit()

print('Yes')


Fixed code:
s = input()
q = [0]
flag = False
while len(s) > 0:
    if s[0:5] in ['dream','erase'] and flag == False:
        q.append(s[0:5])
        s = s[5:]
        flag = False
    elif s[0:6] == 'eraser':
        q.append(s[0:6])
        s = s[6:]
        flag = False
    elif s[0:7] == 'dreamer':
        q.append(s[0:7])
        s = s[7:]
        flag = False
    elif q[-1] in ['dream','erase']:
        s = q[-1] + s
        q.pop()
        flag = True
    else:
        print('NO')
        exit()

print('YES')