4-keys-keyboard

gistfile1.txt

https://discuss.leetcode.com/topic/97628/java-4-lines-recursion-with-step-by-step-explanation-to-derive-dp

public int maxA(int n) {
    int[] dp = new int[n + 1];
    for (int i = 0; i <= n; i++) {
        dp[i] = i;
        for (int j = 1;j <= i - 3; j++) {//dp[j] => with j operations, max num of A we can produce 
            dp[i] = Math.max(dp[i], dp[j] * (i - j - 1));
                                        dp[j] * (i-j-2) + dp[j]
        }    
    }
    return dp[n];
}