剑指offer-把数组排成最小的数python）

思路1：
python2是 num.sort(cmp=lmb)
也可以用lambda n1, n2:int(str(n1)+str(n2))-int(str(n2)+str(n1))表示升序排列
def mycmp1(x,y): #升序排列
return x-y
def mycmp2(x,y)： #降序排列
return y-x

# -*- coding:utf-8 -*-
class Solution:
    def PrintMinNumber(self, numbers):
        # write code here
        if not numbers:
            return ''
        num=list(map(str,numbers))
        num.sort(cmp=lambda x,y:cmp(x+y,y+x))
        return ''.join(num).lstrip('0') or'0'

思路2：暴力

# -*- coding:utf-8 -*-
class Solution:
    def PrintMinNumber(self, numbers):
        # write code here
        if not numbers:
            return ''
        if len(numbers)==1:
            return numbers[0]
        numstr=list(map(str,numbers))
        for i in range(len(numstr)):
            for j in range(1+i,len(numstr)):
                a=int(numstr[i]+numstr[j])
                b=int(numstr[j]+numstr[i])
                if(a>b):
                    t=numstr[i]
                    numstr[i]=numstr[j]
                    numstr[j]=t
        s=""
        for i in range(len(numstr)):
            s+=numstr[i]
        return int(s)