Find all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used and each combination should be a unique set of numbers.
Example 1:
Input: k = 3, n = 7
Output:
[[1,2,4]]
Example 2:
Input: k = 3, n = 9
Output:
[[1,2,6], [1,3,5], [2,3,4]]
Credits:
Special thanks to @mithmatt for adding this problem and creating all test cases.
class Solution:
def combinationSum3(self, k, n):
"""
:type k: int
:type n: int
:rtype: List[List[int]]
"""
res = []
def gen(l, k, n, cur):
if k == len(l) and n == 0:
res.append(l[:])
return
for i in range(cur, 10):
l.append(i)
gen(l, k, n - i, i + 1)
l.pop()
gen([], k, n, 1)
return res
原文地址:https://www.cnblogs.com/xiejunzhao/p/8379834.html
时间: 2024-10-09 09:29:28