diff --git "a/ksinji/202601/PGM 21 \353\213\244\354\235\214 \355\201\260 \354\210\253\354\236\220.md" "b/ksinji/202601/PGM 21 \353\213\244\354\235\214 \355\201\260 \354\210\253\354\236\220.md"
new file mode 100644
index 00000000..9d8c7e2e
--- /dev/null
+++ "b/ksinji/202601/PGM 21 \353\213\244\354\235\214 \355\201\260 \354\210\253\354\236\220.md"	
@@ -0,0 +1,26 @@
+```java
+class Solution {
+    public int solution(int n) {
+        int answer = n+1;
+        int cnt = countOne(n);
+        
+        while (answer > n) {
+            if (countOne(answer) == cnt){
+                break;
+            }
+            answer++;
+        }
+        
+        return answer;
+    }
+    
+    int countOne(int x) {
+        String s = Integer.toBinaryString(x);
+        int cnt = 0;
+        for (int i = 0; i < s.length(); i++) {
+            if (s.charAt(i) == '1') cnt++;
+        }
+        return cnt;
+    }
+}
+```