Leetcode: Combinations @Python

class Solution:
    # @return a list of lists of integers
    def combine(self, n, k):
        rst=[]
        crt=[0 for i in range(k)]
        p=0
        if 0<k<=n:
            while p>=0:
                crt[p]+=1
                for i in range(p+1,k):
                    crt[i]=crt[i-1]+1
                rst.append(crt[:])
                p=k-1
                while p>=0 and crt[p]==n-(k-1-p):
                    p-=1
        return rst

Cheating code:

class Solution:
    # @return a list of lists of integers
    def combine(self, n, k):
        return map(list,list(itertools.combinations(range(1,n+1),k)))