Python/dynamic_programming/sum_of_subset.py
Christian Clauss 9316e7c014
Set the Python file maximum line length to 88 characters ()
* flake8 --max-line-length=88

* fixup! Format Python code with psf/black push

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
2020-06-16 10:09:19 +02:00

38 lines
1.1 KiB
Python

def isSumSubset(arr, arrLen, requiredSum):
"""
>>> isSumSubset([2, 4, 6, 8], 4, 5)
False
>>> isSumSubset([2, 4, 6, 8], 4, 14)
True
"""
# a subset value says 1 if that subset sum can be formed else 0
# initially no subsets can be formed hence False/0
subset = [[False for i in range(requiredSum + 1)] for i in range(arrLen + 1)]
# for each arr value, a sum of zero(0) can be formed by not taking any element
# hence True/1
for i in range(arrLen + 1):
subset[i][0] = True
# sum is not zero and set is empty then false
for i in range(1, requiredSum + 1):
subset[0][i] = False
for i in range(1, arrLen + 1):
for j in range(1, requiredSum + 1):
if arr[i - 1] > j:
subset[i][j] = subset[i - 1][j]
if arr[i - 1] <= j:
subset[i][j] = subset[i - 1][j] or subset[i - 1][j - arr[i - 1]]
# uncomment to print the subset
# for i in range(arrLen+1):
# print(subset[i])
print(subset[arrLen][requiredSum])
if __name__ == "__main__":
import doctest
doctest.testmod()