feat(work): add Minimum Path Sum & Longest Common Subsequence solutions; refactor Unique Paths DP implementation

work/1/Medium/Math/62.unique-paths.py

@@ -43,11 +43,16 @@ Constraints:
 
 class Solution:
     def uniquePaths(self, m: int, n: int) -> int:
-        row = [1] * n
+        dp = [[0 for _ in range(n)] for _ in range(m)]
 
-        for i in range(m - 1):
-            newRow = [1] * n
-            for j in range(n - 2, -1, -1):
-                newRow[j] = newRow[j + 1] + row[j]
-            row = newRow
-        return row[0]
+        for c in range(n):
+            dp[0][c] = 1
+
+        for r in range(m):
+            dp[r][0] = 1
+
+        for r in range(1, m):
+            for c in range(1, n):
+                dp[r][c] = dp[r - 1][c] + dp[r][c - 1]
+
+        return dp[-1][-1]