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Subarray Sum Equals K.py
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Subarray Sum Equals K.py
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class Solution:
def subarraySum(self, nums: List[int], k: int) -> int:
count = 0
for i in range(len(nums)):
if nums[i] == k:
count += 1
sum = nums[i]
for j in range(i+1,len(nums)):
sum += nums[j]
if sum == k:
count +=1
return count
# will work on only +ive numbers
from collections import deque
class Solution:
def subarraySum(self, nums: List[int], k: int) -> int:
queue = deque()
sum , count = 0 , 0
for i in range(len(nums)):
sum += nums[i]
queue.append(i)
while sum > k:
item = queue.popleft()
sum = sum - nums[item]
if sum == k and queue:
count += 1
return count
#Time and Space - O(N)
class Solution:
def subarraySum(self, nums: List[int], k: int) -> int:
result = 0
currentSum = 0
hash_table = {0:1} #no of times sum 0 appearing
for i in range(len(nums)):
currentSum += nums[i]
if currentSum - k in hash_table:
result += hash_table[currentSum-k]
hash_table[currentSum] = hash_table.get(currentSum,0) + 1
return result