Create Solution.py

Author: CodersAcademy006

solution/1300-1399/1307.Verbal Arithmetic Puzzle/Solution.py

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+class Solution:
+    def isAnyMapping(self, words, row, col, bal, letToDig, digToLet, totalRows, totalCols):
+        # If traversed all columns.
+        if col == totalCols:
+            return bal == 0
+
+        # At the end of a particular column.
+        if row == totalRows:
+            return (bal % 10 == 0 and 
+                    self.isAnyMapping(words, 0, col + 1, bal // 10, letToDig, digToLet, totalRows, totalCols))
+
+        w = words[row]
+
+        # If the current string 'w' has no character in the ('col')th index.
+        if col >= len(w):
+            return self.isAnyMapping(words, row + 1, col, bal, letToDig, digToLet, totalRows, totalCols)
+
+        # Take the current character in the variable letter.
+        letter = w[len(w) - 1 - col]
+
+        # Create a variable 'sign' to check whether we have to add it or subtract it.
+        if row < totalRows - 1:
+            sign = 1
+        else:
+            sign = -1
+
+        # If we have a prior valid mapping, then use that mapping.
+        # The second condition is for the leading zeros.
+        if (letter in letToDig and 
+            (letToDig[letter] != 0 or (letToDig[letter] == 0 and len(w) == 1) or col != len(w) - 1)):
+            
+            return self.isAnyMapping(words, row + 1, col, bal + sign * letToDig[letter], 
+                                     letToDig, digToLet, totalRows, totalCols)
+
+        # Choose a new mapping.
+        else:
+            for i in range(10):
+                # If 'i'th mapping is valid then select it.
+                if digToLet[i] == '-' and (i != 0 or (i == 0 and len(w) == 1) or col != len(w) - 1):
+                    digToLet[i] = letter
+                    letToDig[letter] = i
+                    
+                    # Call the function again with the new mapping.
+                    if self.isAnyMapping(words, row + 1, col, bal + sign * letToDig[letter], 
+                                         letToDig, digToLet, totalRows, totalCols):
+                        return True
+
+                    # Unselect the mapping.
+                    digToLet[i] = '-'
+                    if letter in letToDig:
+                        del letToDig[letter]
+
+        # If nothing is correct then just return false.
+        return False
+
+    def isSolvable(self, words, result):
+        # Add the string 'result' in the list 'words'.
+        words.append(result)
+
+        # Initialize 'totalRows' with the size of the list.
+        totalRows = len(words)
+
+        # Find the longest string in the list and set 'totalCols' with the size of that string.
+        totalCols = max(len(word) for word in words)
+
+        # Create a HashMap for the letter to digit mapping.
+        letToDig = {}
+        
+        # Create a list for the digit to letter mapping.
+        digToLet = ['-'] * 10
+
+        return self.isAnyMapping(words, 0, 0, 0, letToDig, digToLet, totalRows, totalCols)
+
+# Example usage:
+sol = Solution()
+
+words1 = ["SEND", "MORE"]
+result1 = "MONEY"
+print(sol.isSolvable(words1, result1))  # Output: True
+
+words2 = ["SIX", "SEVEN", "SEVEN"]
+result2 = "TWENTY"
+print(sol.isSolvable(words2, result2))  # Output: True
+
+words3 = ["LEET", "CODE"]
+result3 = "POINT"
+print(sol.isSolvable(words3, result3))  # Output: False