a solution of 083.2 in python3

1 files changed, 31 insertions, 0 deletions

diff --git a/challenge-083/gugod/python/ch-2.py b/challenge-083/gugod/python/ch-2.py
new file mode 100644
index 0000000000..1a3a3bffc2
--- /dev/null
+++ b/challenge-083/gugod/python/ch-2.py
@@ -0,0 +1,31 @@
+#!/usr/bin/env python3
+import sys
+import itertools
+
+def flipCombination(A):
+    minSum = nSum = sum(A)
+    minCombination = ()
+    for k in range(1, len(A)):
+        for c in itertools.combinations(A, k):
+            s = nSum - 2 * sum(c)
+            if 0 <= s < minSum:
+                minCombination = c
+                minSum = s
+                yield minSum, minCombination
+
+
+def flipElems(A):
+    minSum = sum(A)
+    minCombination = ()
+    for s, c in flipCombination(A):
+        if s < minSum:
+            minSum = s
+            minCombination = c
+        if s == 0:
+            break
+    print(f'>> {minSum} = sum({A}) - 2 * sum({minCombination})')
+    return len(minCombination)
+
+# print(flipElems([2,13,10,8]))   # 2
+# print(flipElems([10,12,2]))   # 1
+print(flipElems(list(map(int, sys.argv[1:]))))