upd

algorithms/labs/lab8/code/dp/1.py

@@ -0,0 +1,14 @@
+def word_break(s, wordDict):
+    dp = [True] + [False] * len(s)
+    for i in range(1, len(s) + 1):
+        for w in wordDict:
+            j = i - len(w)
+            if j >= 0 and dp[j] and s[j:i] == w:
+                dp[i] = True
+                break
+    return dp[-1]
+
+
+if __name__ == "__main__":
+    print(word_break("applepenapple", ["apple", "pen"]))
+    print(word_break("catsandog", ["cats", "dog", "sand", "and", "cat"]))

algorithms/labs/lab8/code/dp/2.py

@@ -0,0 +1,18 @@
+def min_cost_to_win(n):
+    dp = [[0] * (n + 2) for _ in range(n + 2)]
+    for length in range(2, n + 1):
+        for i in range(1, n - length + 2):
+            j = i + length - 1
+            best = 10**9
+            for p in range(i, j + 1):
+                left = dp[i][p - 1] if p > i else 0
+                right = dp[p + 1][j] if p < j else 0
+                best = min(best, p + max(left, right))
+            dp[i][j] = best
+    return dp[1][n]
+
+
+if __name__ == "__main__":
+    print(min_cost_to_win(1))
+    print(min_cost_to_win(2))
+    print(min_cost_to_win(10))

algorithms/labs/lab8/code/dp/3.py

@@ -0,0 +1,14 @@
+def find_max_form(strs, m, n):
+    dp = [[0] * (n + 1) for _ in range(m + 1)]
+    for s in strs:
+        z = s.count("0")
+        o = len(s) - z
+        for i in range(m, z - 1, -1):
+            for j in range(n, o - 1, -1):
+                dp[i][j] = max(dp[i][j], dp[i - z][j - o] + 1)
+    return dp[m][n]
+
+
+if __name__ == "__main__":
+    print(find_max_form(["10", "0001", "111001", "1", "0"], 5, 3))
+    print(find_max_form(["10", "0", "1"], 1, 1))