不作死就不会死--似乎还是元组性能好

def xwhile_stacks(n):
    stacks = [(0,n,None,None,)]
    while stacks:
        stg,n,possible,choice=stacks.pop()
        if stg==0:
            if n==1:
                res = 1,0
            else:
                stacks.append((1,n,[],n-1))
                stacks.append((0,1,None,None))
        else:
            value = 2*res[0] + 2**choice-1
            possible.append((value,choice))
            if choice > 1:
                stacks.append((1,n,possible,choice-1))
                stacks.append((0,n-choice+1,None,None))
            else:
                res = min(possible,key=lambda x:x[0])
    return res

def ywhile_stacks(n):
    stacks = [[0,n]]
    while stacks:
        c=stacks.pop()
        if c[0]==0:
            if c[1]==1:
                res = 1,0
            else:
                c[0]=1
                c.append([])
                c.append(c[1]-1)
                stacks.append(c)
                stacks.append([0,1])
        else:
            value = 2*res[0] + 2**c[3]-1
            c[2].append((value,c[3]))
            if c[3] > 1:
                c[3]=c[3]-1
                stacks.append(c)
                stacks.append([0,c[1]-c[3]])
            else:
                res = min(c[2],key=lambda x:x[0])
    return res

>>> 
1 groups, 10 times
xwhile_stacks best time: 18.310476023494346
ywhile_stacks best time: 23.709957728138697