Create 1130-minimum-cost-tree-from-leaf-values.js

Author: everthis

1130-minimum-cost-tree-from-leaf-values.js

@@ -0,0 +1,20 @@
+/**
+ * @param {number[]} arr
+ * @return {number}
+ */
+const mctFromLeafValues = function(arr) {
+  let res = 0, n = arr.length;
+  let stack = new Array();
+  stack.push(Number.MAX_VALUE);
+  for (let a of arr) {
+    while (stack[stack.length - 1] <= a) {
+      let mid = stack.pop();
+      res += mid * Math.min(stack[stack.length - 1], a);
+    }
+    stack.push(a);
+  }
+  while (stack.length > 2) {
+    res += stack.pop() * stack[stack.length - 1];
+  }
+  return res;   
+};