feat: added alternative python solutions.

longest-palindromic-subsequence/problem.json

@@ -43,7 +43,7 @@
     },
     "solutions": {
         "main-ac": "ac.cpp",
-        "alternative-ac": [],
+        "alternative-ac": ["alternative-ac.py"],
         "wrong-answer": [],
         "time-limit": ["TLE.cpp"],
         "time-limit-or-ac": [],

longest-palindromic-subsequence/src/alternative-ac.py

@@ -0,0 +1,15 @@
+n = int(input())
+s = input().strip()
+
+s_rev = s[::-1]
+
+dp = [[0] * (n + 1) for _ in range(n + 1)]
+
+for i in range(1, n + 1):
+    for j in range(1, n + 1):
+        if s[i - 1] == s_rev[j - 1]:
+            dp[i][j] = dp[i - 1][j - 1] + 1
+        else:
+            dp[i][j] = max(dp[i - 1][j], dp[i][j - 1])
+
+print(dp[n][n])