[20251004] BOJ / G4 / List of Unique Numbers / 이인희

Author: LiiNi-coder

LiiNi-coder/202510/04 BOJ List of Unique Numbers.md

@@ -0,0 +1,33 @@
+```java
+import java.io.*;
+import java.util.*;
+
+public class Main {
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(                                                                                                                                                             new InputStreamReader(System.in));
+        int N = Integer.parseInt(br.readLine());
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        int[] arr = new int[N];
+        for(int i = 0; i < N; i++){
+            arr[i] = Integer.parseInt(st.nextToken());
+        }
+
+        long result = 0;
+        int l = 0;
+        int MAX = 100000;
+
+        int[] freq = new int[MAX + 1];
+        for(int r = 0; r < N; r++){
+            freq[arr[r]]++;
+            while(freq[arr[r]] > 1){
+                freq[arr[l]]--;
+                l++;
+            }
+            result += (r - l +1);
+        }
+
+        System.out.println(result);
+    }
+}
+
+```