題目
Given an array of n positive integers and a positive integer s, find the minimal length of a subarray of which the sum ≥ s. If there isn't one, return 0 instead.
思路
用兩個指針維護(hù)一個滑動框
For example, given the array [2,3,1,2,4,3] and s = 7,
the subarray [4,3] has the minimal length under the problem constraint.
代碼
class Solution:
# @param {integer} s
# @param {integer[]} nums
# @return {integer}
def minSubArrayLen(self, s, nums):
if nums==None or len(nums)==0:
return 0
i = 0
t = 0
min_len = 0
for j in range(len(nums)):
t += nums[j]
print i,j,t
while t >= s:
if j-i+1 < min_len or min_len == 0:
min_len = j-i+1
t -= nums[i]
i += 1
return min_len
