climbing-stairs 문제 답안 제출

Author: jjipper

climbing-stairs/jjipper.ts

@@ -0,0 +1,32 @@
+// https://leetcode.com/problems/climbing-stairs/
+
+// 공간 복잡도 개선 후 풀이
+
+// time complexity : O(n)
+// space complexity : O(1)
+function climbStairs(n: number): number {
+    if (n < 3) {
+        return n;
+    }
+    let pre = 1;
+    let cur = 2;
+    for (let i = 0; i < n - 2; i++) {
+        let temp = pre;
+        pre = cur;
+        cur = temp + pre;
+    }
+    return cur;
+};
+
+// 공간 복잡도 개선 전 풀이
+
+// time complexity : O(n)
+// space complexity : O(n)
+
+// function climbStairs(n: number): number {
+//     const dp = {1: 1, 2: 2}
+//     for (let i = 3; i < n + 1; i++) {
+//         dp[i] = dp[i - 1] + dp[i - 2];
+//     }
+//     return dp[n]
+// };