python 代码

n,m = map(int,input().split())
a = [0] + list(map(int,input().split()))
l = 1
r = n
def check(mid):
    s = a[1:mid + 1]
    s = sorted(s,reverse = True)
    s = [0] + s
    SUM = 0
    i = 1
    for i in range(1,mid + 1,2):
        SUM = SUM + s[i]
    if SUM <= m:
        return True
    else:
        return False
while l < r:
    mid = (l + r + 1) // 2
    if check(mid):
        l = mid
    else:
        r = mid - 1
print(r)