Merge pull request #12185 from ysth/challenge-325-ysth

challenge 325 python and perl solutons by ysth

2 files changed, 76 insertions, 0 deletions

diff --git a/challenge-325/ysth/python/ch-1.py b/challenge-325/ysth/python/ch-1.py
new file mode 100644
index 0000000000..97aa83a7a3
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+++ b/challenge-325/ysth/python/ch-1.py
@@ -0,0 +1,58 @@
+import sys
+
+#https://stackoverflow.com/questions/65271060/is-there-a-built-in-way-to-use-inline-c-code-in-python
+
+# cffi? https://stackoverflow.com/questions/65271060/is-there-a-built-in-way-to-use-inline-c-code-in-python
+# python benchmarks
+
+# ch-2: perl using List::BinarySearch and Judy1
+
+def make_regex_search(r):
+    def regex_search(binary_list):
+        match = r.search(''.join(['1' if value==1 else '0' for value in binary_list]))
+        result = 0 if not match else len(match.group(1))
+        return result
+    return regex_search
+
+import re
+naive_regex = make_regex_search(re.compile('(1+)(?!.*?\\1)'))
+
+better_regex = make_regex_search(re.compile('(?<!1)(1++)(?!.*?\\1)'))
+
+# re does not support branch reset or SKIP, re and regex do not support MARK
+import pcre2
+one_pass_regex = make_regex_search(pcre2.compile('(?|(1++).*?(*MARK:go)\\1(*SKIP:go)(*FAIL)|(1++))'))
+
+def loop(binary_list):
+    current_sequence = 0;
+    longest_sequence = 0;
+    for value in binary_list:
+        if value:
+            current_sequence += 1
+        else:
+            if longest_sequence < current_sequence:
+                longest_sequence = current_sequence
+            current_sequence = 0
+    if longest_sequence < current_sequence:
+        longest_sequence = current_sequence
+    return longest_sequence
+
+def loop_sentinel(binary_list):
+    current_sequence = 0;
+    longest_sequence = 0;
+    for value in (*binary_list, 0):
+        if value:
+            current_sequence += 1
+        else:
+            if longest_sequence < current_sequence:
+                longest_sequence = current_sequence
+            current_sequence = 0
+    return longest_sequence
+
+#binary_list = [1 if value=='1' else 0 for value in sys.argv[1:]]
+from digits import digits as binary_list
+print(loop(binary_list))
+print(loop_sentinel(binary_list))
+print(naive_regex(binary_list))
+print(better_regex(binary_list))
+print(one_pass_regex(binary_list))
diff --git a/challenge-325/ysth/python/ch-2.py b/challenge-325/ysth/python/ch-2.py
new file mode 100644
index 0000000000..f151496925
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+++ b/challenge-325/ysth/python/ch-2.py
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+import sys
+import bisect
+
+prices = [int(value) for value in sys.argv[1:]]
+
+
+sale_prices = []
+seen_prices = []
+for price in reversed(prices):
+    seen_price_index = bisect.bisect_right(seen_prices, price)
+    discount = seen_prices[seen_price_index-1] if seen_price_index > 0 else 0
+    if seen_price_index == 0 or seen_prices[seen_price_index-1] != price:
+        seen_prices[seen_price_index:] = [price]
+    sale_prices.insert(0, price - discount)
+
+
+print("prices: ", prices)
+print("sale prices ", sale_prices)