Add Python solution to challenge 112

3 files changed, 93 insertions, 0 deletions

diff --git a/challenge-112/paulo-custodio/Makefile b/challenge-112/paulo-custodio/Makefile
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+++ b/challenge-112/paulo-custodio/Makefile
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+all:
+	perl ../../challenge-001/paulo-custodio/test.pl
diff --git a/challenge-112/paulo-custodio/python/ch-1.py b/challenge-112/paulo-custodio/python/ch-1.py
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+++ b/challenge-112/paulo-custodio/python/ch-1.py
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+#!/usr/bin/env python3
+
+# Challenge 112
+#
+# TASK #1 - Canonical Path
+# Submitted by: Mohammad S Anwar
+# You are given a string path, starting with a slash '/'.
+#
+# Write a script to convert the given absolute path to the simplified canonical
+# path.
+#
+# In a Unix-style file system:
+#
+# - A period '.' refers to the current directory
+# - A double period '..' refers to the directory up a level
+# - Multiple consecutive slashes ('//') are treated as a single slash '/'
+# The canonical path format:
+#
+# - The path starts with a single slash '/'.
+# - Any two directories are separated by a single slash '/'.
+# - The path does not end with a trailing '/'.
+# - The path only contains the directories on the path from the root directory
+#   to the target file or directory
+# Example
+# Input: "/a/"
+# Output: "/a"
+#
+# Input: "/a/b//c/"
+# Output: "/a/b/c"
+#
+# Input: "/a/b/c/../.."
+# Output: "/a"
+
+import sys
+import re
+
+def canon(path):
+    def replace(srch, rpl, s):
+        while True:
+            s, count = re.subn(srch, rpl, s)
+            if count==0:
+                return s
+
+    path = replace(r"/\./", "/", path)
+    path = replace(r"/\.$", "/", path)
+    path = replace(r"/[^\/\.]+/\.\./", "/", path)
+    path = replace(r"/[^\/\.]+/\.\.$", "/", path)
+    path = re.sub(r"/+", "/", path)
+    path = re.sub(r"/$", "", path)
+    return path
+
+print(canon(sys.argv[1]))
diff --git a/challenge-112/paulo-custodio/python/ch-2.py b/challenge-112/paulo-custodio/python/ch-2.py
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+++ b/challenge-112/paulo-custodio/python/ch-2.py
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+#!/usr/bin/env python3
+
+# Challenge 112
+#
+# TASK #2 - Climb Stairs
+# Submitted by: Mohammad S Anwar
+# You are given $n steps to climb
+#
+# Write a script to find out the distinct ways to climb to the top. You are
+# allowed to climb either 1 or 2 steps at a time.
+#
+# Example
+# Input: $n = 3
+# Output: 3
+#
+#     Option 1: 1 step + 1 step + 1 step
+#     Option 2: 1 step + 2 steps
+#     Option 3: 2 steps + 1 step
+#
+# Input: $n = 4
+# Output: 5
+#
+#     Option 1: 1 step + 1 step + 1 step + 1 step
+#     Option 2: 1 step + 1 step + 2 steps
+#     Option 3: 2 steps + 1 step + 1 step
+#     Option 4: 1 step + 2 steps + 1 step
+#     Option 5: 2 steps + 2 steps
+
+import sys
+
+def count(n):
+    if n <= 0:
+        return 0
+    elif 1 <= n <= 2:
+        return n
+    else:
+        return count(n-1)+count(n-2)
+
+print(count(int(sys.argv[1])))