regular-exp-algo

Algorithms_and_Data_Structures/Dynamic-Programming-Series/Hard-DP-Problems/regular-expression-matching.py

@@ -0,0 +1,24 @@
+def isMatch(s, p):
+    m, n = len(s), len(p)
+
+    # Initialize a (m+1) x (n+1) DP table
+    dp = [[False] * (n + 1) for _ in range(m + 1)]
+
+    dp[0][0] = True
+
+    for j in range(1, n + 1):
+        if p[j - 1] == '*':
+            dp[0][j] = dp[0][j - 2]
+
+    for i in range(1, m + 1):
+        for j in range(1, n + 1):
+            if p[j - 1] == s[i - 1] or p[j - 1] == '.':
+                dp[i][j] = dp[i - 1][j - 1]
+            elif p[j - 1] == '*':
+                dp[i][j] = dp[i][j - 2] or (dp[i - 1][j] and (p[j - 2] == s[i - 1] or p[j - 2] == '.'))
+
+    return dp[m][n]
+
+s = "aab"
+p = "c*a*b"
+print(f"Does '{s}' match the pattern '{p}': {isMatch(s, p)}")