2주차 문제 풀이 2개 추가

- Valid Anagram
- Climbing Stairs

Author: hwi-middle

climbing-stairs/hwi-middle.cpp

@@ -0,0 +1,16 @@
+class Solution {
+public:
+    int climbStairs(int n) {
+        int p = 1;
+        int pp = 0;
+        int cur = 0;
+        for (int i = 0; i < n; ++i)
+        {
+            cur = p + pp;
+            pp = p;
+            p = cur;
+        }
+
+        return cur;
+    }
+};

valid-anagram/hwi-middle.cpp

@@ -0,0 +1,29 @@
+class Solution {
+public:
+    bool isAnagram(string s, string t) {
+        if (s.size() != t.size())
+        {
+            return false;
+        }
+
+        int cnt_s[26];
+        int cnt_t[26];
+        
+        int len = s.size();
+        for (int i = 0; i < len; ++i)
+        {
+            cnt_s[s[i] - 'a']++;
+            cnt_t[t[i] - 'a']++;
+        }
+
+        for (int i = 0; i < 26; ++i)
+        {
+            if(cnt_s[i] != cnt_t[i])
+            {
+                return false;
+            }
+        }
+
+        return true;
+    }
+};