Python/dynamic_programming/sum_of_subset.py
Ankur Chattopadhyay 7592cba417 psf/black code formatting (#1421)
* added sol3.py for problem_20

* added sol4.py for problem_06

* ran `black .` on `\Python`
2019-10-22 19:13:48 +02:00

37 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()