Create 651-4-keys-keyboard.js

Author: everthis

651-4-keys-keyboard.js

@@ -0,0 +1,13 @@
+/**
+ * @param {number} N
+ * @return {number}
+ */
+const maxA = function (N) {
+  const dp = [...new Array(N + 1)].map((_, i) => i)
+  for (let i = 4; i <= N; i++) {
+    for (let j = 1; j <= i - 3; j++) {
+      dp[i] = Math.max(dp[i], dp[j] * (i - j - 1))
+    }
+  }
+  return dp[N]
+}