[20250713] BOJ / G1 / 제곱 ㄴㄴ 수 / 이종환

0224LJH/202507/13 BOJ 제곱 ㄴㄴ 수.md

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+```java
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Arrays;
+import java.util.StringTokenizer;
+
+public class Main {
+    static long ans,max,min;
+    static int len;
+    static boolean[] powerNoNoNum;
+
+    public static void main(String[] args) throws IOException {
+        init();
+        process();
+        print();
+    }
+
+    private static void init() throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        min = Long.parseLong(st.nextToken());
+        max = Long.parseLong(st.nextToken());
+        len = (int) (max - min+1);
+
+        powerNoNoNum = new boolean[len];
+        Arrays.fill(powerNoNoNum,true);
+        ans = 0;
+
+    }
+
+    private static void process() {
+        for (long i = 2; i * i <= max; i++){
+            long powerNum = i * i;
+            if (powerNum > max) break;
+
+            long curIdx;
+            if (powerNum < min) {
+                long temp = (min + powerNum - 1) / powerNum;
+                curIdx = temp * powerNum - min;
+            } else {
+                curIdx = powerNum - min;
+            }
+
+            while(curIdx < len){
+                powerNoNoNum[(int) curIdx] = false;
+                curIdx += powerNum;
+            }
+        }
+
+        for (int i = 0; i < powerNoNoNum.length; i++){
+            if (powerNoNoNum[i]) ans++;
+        }
+    }
+
+
+
+
+    private static void print()  {
+        System.out.println(ans);
+    }
+
+
+
+}
+
+```