[20251106] PGM / LV2 / 롤 케이크 자르기 / 이인희

Author: LiiNi-coder

LiiNi-coder/202511/06 PGM 롤케이크 자르기.md

@@ -0,0 +1,30 @@
+```java
+import java.util.*;
+
+class Solution {
+    public int solution(int[] toppings) {
+        int answer=0;
+        HashMap<Integer, Integer> r = new HashMap<>();
+        for(int topping: toppings){
+            if(!r.containsKey(topping)){
+                r.put(topping, 0);
+            }
+            r.put(topping, r.get(topping)+1);
+        }
+        HashMap<Integer, Integer> l = new HashMap<>();
+        for(int topping: toppings){
+            if(!l.containsKey(topping)){
+                l.put(topping, 0);
+            }
+            l.put(topping, l.get(topping)+1);
+            r.put(topping, r.get(topping)-1);
+            if(r.get(topping) == 0)
+                r.remove(topping);
+            if(l.size() == r.size())
+                answer++;
+        }
+        return answer;
+    }
+    
+}
+```