Create 1641-count-sorted-vowel-strings.js

Author: everthis

1641-count-sorted-vowel-strings.js

@@ -0,0 +1,21 @@
+/**
+ * @param {number} n
+ * @return {number}
+ */
+const countVowelStrings = function (n) {
+  let mem = [1, 1, 1, 1, 1];
+  for (let i = 1; i < n; ++i) {
+    const next = [0, 0, 0, 0, 0];
+    let tmp = 0;
+    for (let j = 4; j >= 0; --j) {
+      tmp += mem[j];
+      next[j] = tmp;
+    }
+    mem = next;
+  }
+  let sum = 0;
+  for (let i of mem) {
+    sum += i;
+  }
+  return sum;
+};