Problem p03854 (python)

Fixed submission:
import sys
sys.setrecursionlimit(100000)

def str_read(s):
    while True:
        if len(s) == 0:
            return True
        else:
            if s[0:5] in ['maerd', 'esare']:
                s = s[5:]
            elif s[0:6] in ['resare']:
                s = s[6:]
            elif s[0:7] in ['remaerd']:
                s = s[7:]
            else:
                return False


si = input()
if str_read(si[::-1]):
    print('YES')
else:
    print('NO')

Buggy submission (verdict: Runtime Error):
import sys
sys.setrecursionlimit(100000)

def str_read(s):

    if len(s) == 0:
        return True
    else:
        flag: bool = False
        if s[0:5] in ['dream', 'erase']:
            flag = flag or str_read(s[5:])
        if s[0:6] in ['eraser']:
            flag = flag or str_read(s[6:])
        if s[0:7] in ['dreamer']:
            flag = flag or str_read(s[7:])
        return flag


si = input()

if str_read(si):
    print('YES')
else:
    print('NO')

Buggy submission (verdict: Runtime Error):

def str_read(s):

    if len(s) == 0:
        return True
    else:
        flag: bool = False
        if s[0:5] in ['dream', 'erase']:
            flag = flag or str_read(s[5:])
        if s[0:6] in ['eraser']:
            flag = flag or str_read(s[6:])
        if s[0:7] in ['dreamer']:
            flag = flag or str_read(s[7:])
        return flag


si = input()

if str_read(si):
    print('YES')
else:
    print('NO')

Buggy submission (verdict: Runtime Error):

def str_read(s):

    if len(s) == 0:
        return True
    else:
        flag = False
        if s[0:5] in ['dream', 'erase']:
            flag = flag or str_read(s[5:])
        if s[0:6] in ['eraser']:
            flag = flag or str_read(s[6:])
        if s[0:7] in ['dreamer']:
            flag = flag or str_read(s[7:])
        return flag


s = input()

if str_read(s):
    print('YES')
else:
    print('NO')

Buggy submission (verdict: Runtime Error):

def str_read(s):

    if len(s) == 0:
        return True
    else:
        flag = False
        if len(s) > 4 and s[0:5] in ['dream', 'erase']:
            flag = flag or str_read(s[5:])
        if len(s) > 5 and s[0:6] in ['eraser']:
            flag = flag or str_read(s[6:])
        if len(s) > 6 and s[0:7] in ['dreamer']:
            flag = flag or str_read(s[7:])
        return flag


s = input()

if str_read(s):
    print('YES')
else:
    print('NO')

Buggy submission (verdict: Runtime Error):

def str_read(s):

    if len(s) == 0:
        return True
    else:
        flag = False
        if len(s) > 4 and s[0:5] in ['dream', 'erase']:
            flag = flag or str_read(s[5:])
        if len(s) > 5 and s[0:6] in['eraser']:
            flag = flag or str_read(s[6:])
        if len(s) > 6 and s[0:7] in['dreamer']:
            flag = flag or str_read(s[7:])
        return flag


s = input()

if str_read(s):
    print('YES')
else:
    print('NO')

Buggy submission (verdict: Runtime Error):

def str_read(s):

    if len(s) == 0:
        return True
    else:
        flag = False
        if len(s) > 4 and s[0:5] in ['dream', 'erase']:
            flag = flag or str_read(s[5:])
        if len(s) > 5 and s[0:6] in['eraser']:
            flag = flag or str_read(s[6:])
        if len(s) > 6 and s[0:7] in['dreamer']:
            flag = flag or str_read(s[7:])
        return flag


s = input()

if str_read(s):
    print('Yes')
else:
    print('No')