Change longest common substring to subsequence (#196)

2026-03-04 14:48:45 +00:00 · 2017-05-29 20:50:39 -04:00
parent 9f89a51aba
commit 00673c0bfd
6 changed files with 52 additions and 52 deletions
--- a/recursion_dynamic/longest_common_subsequence/init.py
+++ b/recursion_dynamic/longest_common_subsequence/init.py
--- a/recursion_dynamic/longest_common_subsequence/longest_common_subseq_challenge.ipynb
+++ b/recursion_dynamic/longest_common_subsequence/longest_common_subseq_challenge.ipynb
@@ -18,7 +18,7 @@
   "cell_type": "markdown",
   "metadata": {},
   "source": [
-    "## Problem: Given two strings, find the longest common substring.\n",
+    "## Problem: Given two strings, find the longest common subsequence.\n",
    "\n",
    "* [Constraints](#Constraints)\n",
    "* [Test Cases](#Test-Cases)\n",
@@ -40,7 +40,7 @@
    "    * Yes\n",
    "* Is this case sensitive?\n",
    "    * Yes\n",
-    "* Is a substring a contiguous block of chars?\n",
+    "* Is a subsequence a non-contiguous block of chars?\n",
    "    * Yes\n",
    "* Do we expect a string as a result?\n",
    "    * Yes\n",
@@ -90,7 +90,7 @@
   "source": [
    "class StringCompare(object):\n",
    "\n",
-    "    def longest_common_substr(self, str0, str1):\n",
+    "    def longest_common_subseq(self, str0, str1):\n",
    "        # TODO: Implement me\n",
    "        pass"
   ]
@@ -117,26 +117,26 @@
   },
   "outputs": [],
   "source": [
-    "# %load test_longest_common_substr.py\n",
+    "# %load test_longest_common_subseq.py\n",
    "from nose.tools import assert_equal, assert_raises\n",
    "\n",
    "\n",
-    "class TestLongestCommonSubstr(object):\n",
+    "class TestLongestCommonSubseq(object):\n",
    "\n",
-    "    def test_longest_common_substr(self):\n",
+    "    def test_longest_common_subseq(self):\n",
    "        str_comp = StringCompare()\n",
-    "        assert_raises(TypeError, str_comp.longest_common_substr, None, None)\n",
-    "        assert_equal(str_comp.longest_common_substr('', ''), '')\n",
+    "        assert_raises(TypeError, str_comp.longest_common_subseq, None, None)\n",
+    "        assert_equal(str_comp.longest_common_subseq('', ''), '')\n",
    "        str0 = 'ABCDEFGHIJ'\n",
    "        str1 = 'FOOBCDBCDE'\n",
    "        expected = 'BCDE'\n",
-    "        assert_equal(str_comp.longest_common_substr(str0, str1), expected)\n",
-    "        print('Success: test_longest_common_substr')\n",
+    "        assert_equal(str_comp.longest_common_subseq(str0, str1), expected)\n",
+    "        print('Success: test_longest_common_subseq')\n",
    "\n",
    "\n",
    "def main():\n",
-    "    test = TestLongestCommonSubstr()\n",
-    "    test.test_longest_common_substr()\n",
+    "    test = TestLongestCommonSubseq()\n",
+    "    test.test_longest_common_subseq()\n",
    "\n",
    "\n",
    "if __name__ == '__main__':\n",
--- a/recursion_dynamic/longest_common_subsequence/longest_common_subseq_solution.ipynb
+++ b/recursion_dynamic/longest_common_subsequence/longest_common_subseq_solution.ipynb
@@ -18,7 +18,7 @@
   "cell_type": "markdown",
   "metadata": {},
   "source": [
-    "## Problem: Given two strings, find the longest common substring.\n",
+    "## Problem: Given two strings, find the longest common subsequence.\n",
    "\n",
    "* [Constraints](#Constraints)\n",
    "* [Test Cases](#Test-Cases)\n",
@@ -39,7 +39,7 @@
    "    * Yes\n",
    "* Is this case sensitive?\n",
    "    * Yes\n",
-    "* Is a substring a contiguous block of chars?\n",
+    "* Is a subsequence a non-contiguous block of chars?\n",
    "    * Yes\n",
    "* Do we expect a string as a result?\n",
    "    * Yes\n",
@@ -123,7 +123,7 @@
   "source": [
    "class StringCompare(object):\n",
    "\n",
-    "    def longest_common_substr(self, str0, str1):\n",
+    "    def longest_common_subseq(self, str0, str1):\n",
    "        if str0 is None or str1 is None:\n",
    "            raise TypeError('str input cannot be None')\n",
    "        # Add one to number of rows and cols for the dp table's\n",
@@ -143,7 +143,7 @@
    "        results = ''\n",
    "        i = num_rows - 1\n",
    "        j = num_cols - 1\n",
-    "        # Walk backwards to determine the substring\n",
+    "        # Walk backwards to determine the subsequence\n",
    "        while T[i][j]:\n",
    "            if T[i][j] == T[i][j - 1]:\n",
    "                j -= 1\n",
@@ -177,31 +177,31 @@
     "name": "stdout",
     "output_type": "stream",
     "text": [
-      "Overwriting test_longest_common_substr.py\n"
+      "Overwriting test_longest_common_subseq.py\n"
     ]
    }
   ],
   "source": [
-    "%%writefile test_longest_common_substr.py\n",
+    "%%writefile test_longest_common_subseq.py\n",
    "from nose.tools import assert_equal, assert_raises\n",
    "\n",
    "\n",
-    "class TestLongestCommonSubstr(object):\n",
+    "class TestLongestCommonSubseq(object):\n",
    "\n",
-    "    def test_longest_common_substr(self):\n",
+    "    def test_longest_common_subseq(self):\n",
    "        str_comp = StringCompare()\n",
-    "        assert_raises(TypeError, str_comp.longest_common_substr, None, None)\n",
-    "        assert_equal(str_comp.longest_common_substr('', ''), '')\n",
+    "        assert_raises(TypeError, str_comp.longest_common_subseq, None, None)\n",
+    "        assert_equal(str_comp.longest_common_subseq('', ''), '')\n",
    "        str0 = 'ABCDEFGHIJ'\n",
    "        str1 = 'FOOBCDBCDE'\n",
    "        expected = 'BCDE'\n",
-    "        assert_equal(str_comp.longest_common_substr(str0, str1), expected)\n",
-    "        print('Success: test_longest_common_substr')\n",
+    "        assert_equal(str_comp.longest_common_subseq(str0, str1), expected)\n",
+    "        print('Success: test_longest_common_subseq')\n",
    "\n",
    "\n",
    "def main():\n",
-    "    test = TestLongestCommonSubstr()\n",
-    "    test.test_longest_common_substr()\n",
+    "    test = TestLongestCommonSubseq()\n",
+    "    test.test_longest_common_subseq()\n",
    "\n",
    "\n",
    "if __name__ == '__main__':\n",
@@ -219,12 +219,12 @@
     "name": "stdout",
     "output_type": "stream",
     "text": [
-      "Success: test_longest_common_substr\n"
+      "Success: test_longest_common_subseq\n"
     ]
    }
   ],
   "source": [
-    "%run -i test_longest_common_substr.py"
+    "%run -i test_longest_common_subseq.py"
   ]
  }
 ],
--- a/recursion_dynamic/longest_common_subsequence/test_longest_common_subseq.py
+++ b/recursion_dynamic/longest_common_subsequence/test_longest_common_subseq.py
@@ -0,0 +1,23 @@
+from nose.tools import assert_equal, assert_raises
+
+
+class TestLongestCommonSubseq(object):
+
+    def test_longest_common_subseq(self):
+        str_comp = StringCompare()
+        assert_raises(TypeError, str_comp.longest_common_subseq, None, None)
+        assert_equal(str_comp.longest_common_subseq('', ''), '')
+        str0 = 'ABCDEFGHIJ'
+        str1 = 'FOOBCDBCDE'
+        expected = 'BCDE'
+        assert_equal(str_comp.longest_common_subseq(str0, str1), expected)
+        print('Success: test_longest_common_subseq')
+
+
+def main():
+    test = TestLongestCommonSubseq()
+    test.test_longest_common_subseq()
+
+
+if __name__ == '__main__':
+    main()
--- a/recursion_dynamic/longest_common_substring/test_longest_common_substr.py
+++ b/recursion_dynamic/longest_common_substring/test_longest_common_substr.py
@@ -1,23 +0,0 @@
-from nose.tools import assert_equal, assert_raises
-
-
-class TestLongestCommonSubstr(object):
-
-    def test_longest_common_substr(self):
-        str_comp = StringCompare()
-        assert_raises(TypeError, str_comp.longest_common_substr, None, None)
-        assert_equal(str_comp.longest_common_substr('', ''), '')
-        str0 = 'ABCDEFGHIJ'
-        str1 = 'FOOBCDBCDE'
-        expected = 'BCDE'
-        assert_equal(str_comp.longest_common_substr(str0, str1), expected)
-        print('Success: test_longest_common_substr')
-
-
-def main():
-    test = TestLongestCommonSubstr()
-    test.test_longest_common_substr()
-
-
-if __name__ == '__main__':
-    main()