Added last 2 solutions

Author: nhistory

climbing-stairs/nhistory.js

@@ -0,0 +1,20 @@
+/**
+ * @param {number} n
+ * @return {number}
+ */
+var climbStairs = function (n) {
+  // Make an array to store each number of ways
+  let steps = new Array(n);
+  // When stairs is 1 and 2 has exact number 1 and 2
+  steps[1] = 1;
+  steps[2] = 2;
+  // Iterate to get ways of 3 more steps stairs
+  // ((n-1) + (n-2))
+  for (let i = 3; i <= n; i++) {
+    steps[i] = steps[i - 1] + steps[i - 2];
+  }
+  return steps[n];
+};
+
+// TC: O(n)
+// SC: O(n)

meeting-rooms/nhistory.js

@@ -0,0 +1,32 @@
+/**
+ * Definition of Interval:
+ * class Interval {
+ *   constructor(start, end) {
+ *     this.start = start;
+ *     this.end = end;
+ *   }
+ * }
+ */
+
+class Solution {
+  /**
+   * @param {Interval[]} intervals
+   * @returns {boolean}
+   */
+  canAttendMeetings(intervals) {
+    // Sort the intervals based on their start times
+    intervals.sort((a, b) => a.start - b.start);
+
+    for (let i = 0; i < intervals.length - 1; i++) {
+      // Check if the current interval overlaps with the next interval
+      if (intervals[i].end > intervals[i + 1].start) {
+        return false;
+      }
+    }
+
+    return true;
+  }
+}
+
+// TC: O(nlogn)
+// SC: O(1)