Python/dynamic_programming/minimum_partition.py

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"""
Partition a set into two subsets such that the difference of subset sums is minimum
"""
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def find_min(arr: list[int]) -> int:
"""
>>> find_min([1, 2, 3, 4, 5])
1
>>> find_min([5, 5, 5, 5, 5])
5
>>> find_min([5, 5, 5, 5])
0
>>> find_min([3])
3
>>> find_min([])
0
"""
n = len(arr)
s = sum(arr)
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dp = [[False for x in range(s + 1)] for y in range(n + 1)]
for i in range(n + 1):
dp[i][0] = True
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for i in range(1, s + 1):
dp[0][i] = False
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for i in range(1, n + 1):
for j in range(1, s + 1):
dp[i][j] = dp[i - 1][j]
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if arr[i - 1] <= j:
dp[i][j] = dp[i][j] or dp[i - 1][j - arr[i - 1]]
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for j in range(int(s / 2), -1, -1):
if dp[n][j] is True:
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diff = s - 2 * j
break
return diff
if __name__ == "__main__":
from doctest import testmod
testmod()