Merge pull request #9292 from choroba/ech249

Add solutions to 249: Equal Pairs & DI String Match by E. Choroba

2 files changed, 43 insertions, 0 deletions

diff --git a/challenge-249/e-choroba/python/ch-1.py b/challenge-249/e-choroba/python/ch-1.py
new file mode 100755
index 0000000000..8804c18a26
--- /dev/null
+++ b/challenge-249/e-choroba/python/ch-1.py
@@ -0,0 +1,20 @@
+#! /usr/bin/python3
+from collections import Counter
+
+def equal_pairs(*ints):
+    seen = Counter(ints)
+    pairs = []
+    for c in seen:
+        if seen[c] % 2 == 1:
+            return []
+        else:
+            pairs += map(lambda _i: [c, c], range(seen[c] // 2))
+    return pairs
+
+assert equal_pairs(3, 2, 3, 2, 2, 2) == [[3, 3], [2, 2], [2, 2]], 'Example 1'
+assert equal_pairs(1, 2, 3, 4) == [], 'Example 2'
+assert equal_pairs(-1, -1, -2, -2) == [[-1, -1], [-2, -2]], 'Negative numbers'
+assert equal_pairs(1, 1, 1, 1, 2, 2, 2, 2) == [
+    [1, 1], [1, 1], [2, 2], [2, 2]], \
+    'More than once'
+assert equal_pairs(1, 1, 1, 1, 2, 2, 2, 2, 1) == [], 'More than once odd';
diff --git a/challenge-249/e-choroba/python/ch-2.py b/challenge-249/e-choroba/python/ch-2.py
new file mode 100755
index 0000000000..9cff6bee20
--- /dev/null
+++ b/challenge-249/e-choroba/python/ch-2.py
@@ -0,0 +1,23 @@
+#! /usr/bin/python3
+class DiStringMatch:
+    def __init__(self):
+        self.p = [0]
+        self.mx = 1
+
+    def process(self, s):
+        def inc():
+            self.p.append(self.mx)
+            self.mx += 1
+
+        def dec():
+            self.p = [x + 1 for x in self.p]
+            self.mx += 1
+            self.p.append(0)
+
+        for ch in s:
+            inc() if ch == 'I' else dec()
+        return self.p
+
+assert DiStringMatch().process('IDID') == [2, 3, 1, 4, 0]
+assert DiStringMatch().process('III')  == [0, 1, 2, 3]
+assert DiStringMatch().process('DDI')  == [2, 1, 0, 3]