Taste

def checkoperations(l,maxt,op):
    yes = 0
    for p in range(n // 2 - (n + 1) % 2, n):
        if (maxt - l[p] > 0):
            yes = yes + (maxt - l[p])
            if (yes > op):
                return False
    if (yes<op+1):
        return True
    else:
        return False
n=int(input())
k=int(input())
a=[]
for i in range(n):
    a.append(int(input()))
a.sort()
start=1
end=k+max(a)
while start<end+1:
    maxtaste = (start + end)//2
    if (checkoperations(a,maxtaste, k)):
        start = maxtaste + 1
    else :
        end = maxtaste - 1
    answer=start-1
print(answer)