Sliding Window (clever)
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# Find the maximum sum of a subarray of size k.
# Example:
# Input: nums = [2, 1, 5, 1, 3, 2], k = 3
# Output: 9
# source: https://blog.algomaster.io/p/15-leetcode-patterns
def calculate(nums, k):
# clever: sliding window
# calculate first window:
max_sum = 0
sum=0
for i, val in enumerate(nums):
if i==0:
for val in nums[:k]:
sum+=val
print(f"first window={sum}")
elif len(nums)-i<k:
print("break")
break
else:
sum = sum - nums[i-1] + nums[i+k-1]
print(f"next window={sum}")
if sum > max_sum:
max_sum=sum
return max_sum
print("Hello World")
test_case1_array = [2, 1, 5, 1, 3, 2]
test_case1_wind_size = 3
result1 = calculate(test_case1_array, test_case1_wind_size)
print(f"result1={result1}")
assert(result1==9)
test_case2_array = [2, 1, 11, 5, 1, 3, -12, 18, 8]
# 19, 18, 20, -3, 10, 17
test_case2_wind_size = 4
result2 = calculate(test_case2_array, test_case2_wind_size)
print(f"result1={result2}")
assert(result2==20)
print("Good-Bye CruelWorld")
Python
INFO