Buggy python submission (verdict: Runtime Error):
from collections import deque
from heapq import heapify,heappop,heappush,heappushpop
from copy import copy,deepcopy
from itertools import permutations,combinations
from collections import defaultdict,Counter
from bisect import bisect_left,bisect_right
# from math import gcd,ceil,floor,factorial
# from fractions import gcd
from functools import reduce
from pprint import pprint

def myinput():
    return map(int,input().split())

def mylistinput(n):
    return [ list(myinput()) for _ in range(n) ]

def mycol(data,col):
    return [ row[col] for row in data ]

def mysort(data,col,reverse_flag):
    data.sort(key=lambda x:x[col],reverse=reverse_flag)
    return data

def mymax(data):
    M = -1*float("inf")
    for i in range(len(data)):
        m = max(data[i])
        M = max(M,m)
    return M

def mymin(data):
    m = float("inf")
    for i in range(len(data)):
        M = min(data[i])
        m = min(m,M)
    return m

def myoutput(ls,space=True):
    if space:
        if len(ls)==0:
            print(" ")
        elif type(ls[0])==str:
            print(" ".join(ls))
        elif type(ls[0])==int:
            print(" ".join(map(str,ls)))
        else:
            print("Output Error")
    else:
        if len(ls)==0:
            print("")
        elif type(ls[0])==str:
            print("".join(ls))
        elif type(ls[0])==int:
            print("".join(map(str,ls)))
        else:
            print("Output Error")

# ----- heapq ここから-----
import heapq
class Reverse:
    def __init__(self, val):
        self.val = val
        
    def __lt__(self, other):
        return self.val > other.val
        
    def __repr__(self):
        return repr(self.val)
    
class Heapq:
    def __init__(self, arr, desc = False):
        if desc:
            for i in range(len(arr)):
                arr[i] = Reverse(arr[i])
        self.desc = desc
        self.hq = arr
        heapq.heapify(self.hq)
 
    def pop(self):
        if self.desc: return heapq.heappop(self.hq).val
        else: return heapq.heappop(self.hq)
 
    def push(self, a):
        if self.desc: heapq.heappush(self.hq, Reverse(a))
        else: heapq.heappush(self.hq, a)
 
    def top(self):
        if self.desc: self.hq[0].val
        else: return self.hq[0]
# ----- heapq ここまで-----

n,k = myinput()
v = list(myinput())
vr = v[::-1]

ans = -float("inf")
for a in range(k+1):
    for b in range(k-a+1):
        have = []
        have.extend( v[:a] )
        have.extend( vr[:b] )
        p = [ i for i in have if i>=0 ]
        m = [ i for i in have if i<0 ]
        m.sort()
        r = k - a - b
        if len(m)!=0
            m = m[r:]
        else:
            m = []
        ans_tmp = sum(p)+sum(m)
        ans = max(ans,ans_tmp)

print(ans)

Fixed submission:
from collections import deque
from heapq import heapify,heappop,heappush,heappushpop
from copy import copy,deepcopy
from itertools import permutations,combinations
from collections import defaultdict,Counter
from bisect import bisect_left,bisect_right
# from math import gcd,ceil,floor,factorial
# from fractions import gcd
from functools import reduce
from pprint import pprint

def myinput():
    return map(int,input().split())

def mylistinput(n):
    return [ list(myinput()) for _ in range(n) ]

def mycol(data,col):
    return [ row[col] for row in data ]

def mysort(data,col,reverse_flag):
    data.sort(key=lambda x:x[col],reverse=reverse_flag)
    return data

def mymax(data):
    M = -1*float("inf")
    for i in range(len(data)):
        m = max(data[i])
        M = max(M,m)
    return M

def mymin(data):
    m = float("inf")
    for i in range(len(data)):
        M = min(data[i])
        m = min(m,M)
    return m

def myoutput(ls,space=True):
    if space:
        if len(ls)==0:
            print(" ")
        elif type(ls[0])==str:
            print(" ".join(ls))
        elif type(ls[0])==int:
            print(" ".join(map(str,ls)))
        else:
            print("Output Error")
    else:
        if len(ls)==0:
            print("")
        elif type(ls[0])==str:
            print("".join(ls))
        elif type(ls[0])==int:
            print("".join(map(str,ls)))
        else:
            print("Output Error")

# ----- heapq ここから-----
import heapq
class Reverse:
    def __init__(self, val):
        self.val = val
        
    def __lt__(self, other):
        return self.val > other.val
        
    def __repr__(self):
        return repr(self.val)
    
class Heapq:
    def __init__(self, arr, desc = False):
        if desc:
            for i in range(len(arr)):
                arr[i] = Reverse(arr[i])
        self.desc = desc
        self.hq = arr
        heapq.heapify(self.hq)
 
    def pop(self):
        if self.desc: return heapq.heappop(self.hq).val
        else: return heapq.heappop(self.hq)
 
    def push(self, a):
        if self.desc: heapq.heappush(self.hq, Reverse(a))
        else: heapq.heappush(self.hq, a)
 
    def top(self):
        if self.desc: self.hq[0].val
        else: return self.hq[0]
# ----- heapq ここまで-----

n,k = myinput()
v = list(myinput())
vr = v[::-1]

ls = [-1,-1]
ans = -float("inf")
for a in range(k+1):
    for b in range(min(k-a+1,n-a+1)):
        have = []
        have.extend( v[:a] )
        have.extend( vr[:b] )
        p = [ i for i in have if i>=0 ]
        m = [ i for i in have if i<0 ]
        m.sort()
        r = k - a - b
        m = m[r:]
        ans_tmp = sum(p)+sum(m)
        if ans<ans_tmp:
            ls[0] = a
            ls[1] = b
        ans = max(ans,ans_tmp)
# print(ls)
print(ans)