1320_Minimum_Distance_to_Type_a_Word_Using_Two_Fingers

Author: Partho Biswas

README.md

@@ -640,7 +640,7 @@ BFS, DFS, Dijkstra, Floyd–Warshall, Bellman-Ford, Kruskal, Prim's, Minimum Spa
 |45| **[975. Odd Even Jump](https://tinyurl.com/y5ovyklj)** | [Python](https://tinyurl.com/wu6rdaw/975_Odd_Even_Jump.py), [Swift](https://tinyurl.com/wuja3c4/975_Odd_Even_Jump.swift)| [Vid 1](https://tinyurl.com/vxyed3g), **[Art 1](https://tinyurl.com/wbjrnyt)** | Hard | DP using stack. Vary tricky and Interesting problem, loved it |
 |46| **[562. Longest Line of Consecutive One in Matrix](https://tinyurl.com/u2fb4a6)** | [Python](https://tinyurl.com/wu6rdaw/562_Longest_Line_of_Consecutive_One_in_Matrix.py), [Swift](https://tinyurl.com/wuja3c4/562_Longest_Line_of_Consecutive_One_in_Matrix.swift)| [Art 1](https://tinyurl.com/vqppbae), [Art 2](https://tinyurl.com/t3xtfq8) | Medium |  |
 |47| **[552. Student Attendance Record II](https://tinyurl.com/tnxj5oa)** | [Python](https://tinyurl.com/wu6rdaw/552_Student_Attendance_Record_II.py), [Swift](https://tinyurl.com/wuja3c4/552_Student_Attendance_Record_II.swift)| [Art 1](https://tinyurl.com/rdt2cgr), [Art 2](https://tinyurl.com/s8okmdb), [Art 3](https://tinyurl.com/uhggppt) | Hard | **This is a FUCKING difficult DP problem. Don't dare to solve it** |
-|48| **[1320. Minimum Distance to Type a Word Using Two Fingers](https://tinyurl.com/ur876a6)** | [Python](https://tinyurl.com/wu6rdaw/1320_Minimum_Distance_to_Type_a_Word_Using_Two_Fingers.py), [Swift](https://tinyurl.com/wuja3c4/1320_Minimum_Distance_to_Type_a_Word_Using_Two_Fingers.swift)| [Vid 1](https://tinyurl.com/u5fcb3z), [Art 2](https://tinyurl.com/s8okmdb), [Art 3](https://tinyurl.com/uhggppt) | Hard | **Important. TODO: Check again** |
+|48| **[1320. Minimum Distance to Type a Word Using Two Fingers](https://tinyurl.com/ur876a6)** | [Python](https://tinyurl.com/wu6rdaw/1320_Minimum_Distance_to_Type_a_Word_Using_Two_Fingers.py), [Swift](https://tinyurl.com/wuja3c4/1320_Minimum_Distance_to_Type_a_Word_Using_Two_Fingers.swift)| [Vid 1](https://tinyurl.com/u5fcb3z), [Art 1](https://tinyurl.com/w386adm), [Art 2](https://tinyurl.com/rnkbhp3), [Art 3](https://tinyurl.com/tqwgraz), [Art 4](https://tinyurl.com/v46fuzm) | Hard | **Important. TODO: Check again** |
 
 
 </p>
@@ -1077,7 +1077,7 @@ Learn the following modules by heart. Just knowing all of the following items wi
 03. [Union Find \[Disjoint Set\] Playlist](https://tinyurl.com/srz7uua)
 04. [Disjoint Sets Data Structure - Weighted Union and Collapsing Find](https://www.youtube.com/watch?v=wU6udHRIkcc)
 05. [Codinginterviewclass.com](https://tinyurl.com/wpgl4nt)
-06. Single/All Source Shortest Path Algorithms: Dijkstra ([1](https://tinyurl.com/r8omw8l), [2](https://tinyurl.com/sscslz7)), Bellman-Ford([1](https://tinyurl.com/tghcsmz), [2](https://tinyurl.com/rdcax5b)), Floyd–Warshall([1](https://tinyurl.com/vsp4ulb), [2](https://tinyurl.com/s5wjb5a))
+06. Single(Di-Bel)/All(Flo) Source Shortest Path Algorithms: Dijkstra ([1](https://tinyurl.com/r8omw8l), [2](https://tinyurl.com/sscslz7)), Bellman-Ford([1](https://tinyurl.com/tghcsmz), [2](https://tinyurl.com/rdcax5b)), Floyd–Warshall([1](https://tinyurl.com/vsp4ulb), [2](https://tinyurl.com/s5wjb5a))
 07. Dijkstra’s Algorithm Vs Bellman-Ford Algorithm Vs Floyd Warshall Algorithm ( [1](https://tinyurl.com/vxwc2je), [2](https://tinyurl.com/s6vff87), [3](https://tinyurl.com/s5o57nz) )
 08. Minimum Spanning Tree Algorithm: Prim's ( [1](https://tinyurl.com/vgbgdl2), [2](https://tinyurl.com/yecuqtty), Kruskal's ([1](https://tinyurl.com/vgbgdl2), [2](https://tinyurl.com/yhxpvpkn) )
 09. Kruskal's algorithm Vs Prim's algorithm ( [1](https://qr.ae/TSEPGc), [2](https://tinyurl.com/yz6399ck), [3](https://tinyurl.com/yz3q7vox) )

leetcode.com/python/1320_Minimum_Distance_to_Type_a_Word_Using_Two_Fingers.py

@@ -0,0 +1,36 @@
+# https://tinyurl.com/u5fcb3z
+# Approach 1: Top-Down DFS with memoization, DP
+import string
+class Solution(object):
+    def minimumDistance(self, word):
+        """
+        :type word: str
+        :rtype: int
+        """
+        # Preprocessing
+        alphabet = string.ascii_uppercase
+        keyboardDict = {}
+        for idx, char in enumerate(alphabet):
+            keyboardDict[char] = (idx // 6, idx % 6)
+        memo = {}
+        return self.minimumDistanceHelper(word, keyboardDict, memo, 0, None, None)
+
+
+    def minimumDistanceHelper(self, word, keyboard, memo, nextCharPosition, currentFingure1Char, currentFingure2Char):
+        if nextCharPosition >= len(word):   # we have processed all the character and we have reached the end
+            return 0
+        if (nextCharPosition, currentFingure1Char, currentFingure2Char) in memo:
+            return memo[(nextCharPosition, currentFingure1Char, currentFingure2Char)]
+
+        choice1 = self.distance(currentFingure1Char, word[nextCharPosition], keyboard) + self.minimumDistanceHelper(word, keyboard, memo, nextCharPosition + 1, word[nextCharPosition], currentFingure2Char) # we  are moving finger 1 here, finger 2 stays still
+        choice2 = self.distance(currentFingure2Char, word[nextCharPosition], keyboard) + self.minimumDistanceHelper(word, keyboard, memo, nextCharPosition + 1, currentFingure1Char, word[nextCharPosition]) # we  are moving finger 2 here, finger 1 stays still
+        memo[(nextCharPosition, currentFingure1Char, currentFingure2Char)] = min(choice1, choice2)
+        return memo[(nextCharPosition, currentFingure1Char, currentFingure2Char)]
+
+
+    def distance(self, startChar,  destChar, keyboard):
+        if startChar is None:
+            return 0
+        x1, y1 = keyboard[startChar]
+        x2, y2 = keyboard[destChar]
+        return abs(x1 - x2) + abs(y1 - y2)