D
DevExCode

LeetCode 464: Can I Win Solution

Master LeetCode problem 464 (Can I Win), a medium challenge, with our optimized solutions in Java, C++, and Python. Explore detailed explanations, test your code in our interactive editor, and prepare for coding interviews.

Problem Explanation

Explanation

To solve this problem, we can use a recursive approach with memoization to keep track of the states and avoid recomputation. We can simulate the game by trying all possible moves at each step and check if any move leads to a win. We need to consider the current total, the remaining numbers available, and the player taking the turn.

  1. Create a hashmap to store the state as the key and the result (win or lose) as the value.
  2. Define a recursive function canWin that takes the current total and the set of remaining numbers.
  3. Check if the current state is already computed in the hashmap, return the result if it exists.
  4. Iterate through all available numbers.
  5. For each number, if it is not used yet, check if the opponent loses by choosing that number.
  6. If the opponent loses, mark the current player as a winner and return true.
  7. If no winning move is found, mark the current player as a loser and return false.
  8. Update the hashmap with the current state and the result.
  9. Call the canWin function with the initial total and the set of all numbers.
  10. Return the result of the function.

Solution Code

class Solution {
    public boolean canIWin(int maxChoosableInteger, int desiredTotal) {
        if (maxChoosableInteger * (maxChoosableInteger + 1) / 2 < desiredTotal) return false;
        return canWin(desiredTotal, (1 << maxChoosableInteger) - 1, new HashMap<>());
    }

    private boolean canWin(int total, int state, Map<Integer, Boolean> memo) {
        if (total <= 0) return false;
        if (memo.containsKey(state)) return memo.get(state);

        for (int i = 0; i < 20; i++) {
            if ((state & (1 << i)) > 0) {
                if (!canWin(total - i - 1, state & ~(1 << i), memo)) {
                    memo.put(state, true);
                    return true;
                }
            }
        }

        memo.put(state, false);
        return false;
    }
}

Try It Yourself

Loading code editor...

Related LeetCode Problems

Frequently Asked Questions

How to solve LeetCode 464 (Can I Win)?

This page provides optimized solutions for LeetCode problem 464 (Can I Win) in Java, C++, and Python, along with a detailed explanation and an interactive code editor to test your code.

What is the time complexity of LeetCode 464 (Can I Win)?

The time complexity for LeetCode 464 (Can I Win) varies by solution. Check the detailed explanation section for specific complexities in Java, C++, and Python implementations.

Can I run code for LeetCode 464 on DevExCode?

Yes, DevExCode provides an interactive code editor where you can write, test, and run your code for LeetCode 464 in Java, C++, or Python.

Back to LeetCode Solutions