[20251028] BOJ / G5 / Hello World! / 김민진

Author: zinnnn37

zinnnn37/202510/28 BOJ G5 Hello World!.md

@@ -0,0 +1,74 @@
+```java
+import java.io.*;
+
+public class BJ_13140_Hello_World {
+
+    private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    private static final BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
+    private static final StringBuilder sb = new StringBuilder();
+
+    private static int N, hello, world;
+    private static int[] nums;
+    private static boolean[] isSelected;
+
+    public static void main(String[] args) throws IOException {
+        init();
+        sol(0);
+
+        bw.write("No Answer");
+        bw.flush();
+        bw.close();
+        br.close();
+    }
+
+    private static void init() throws IOException {
+        N = Integer.parseInt(br.readLine());
+
+        nums = new int[7];
+        isSelected = new boolean[10];
+    }
+
+    private static void sol(int depth) throws IOException {
+        if (depth == 7) {
+            calc();
+            return;
+        }
+
+        for (int i = 0; i < 10; i++) {
+            if (isSelected[i]) continue;
+            if ((depth == 0 || depth == 4) && i == 0) continue;
+
+            nums[depth] = i;
+            isSelected[i] = true;
+            sol(depth + 1);
+            isSelected[i] = false;
+        }
+    }
+
+    private static void calc() throws IOException {
+        int ans = 0;
+
+        hello = nums[0] * 10000 + nums[1] * 1000 + nums[2] * 110 + nums[3];
+        world = nums[4] * 10000 + nums[3] * 1000 + nums[5] * 100 + nums[2] * 10 + nums[6];
+
+        ans = hello + world;
+
+        if (ans == N) {
+            print();
+            System.exit(0);
+        }
+    }
+
+    private static void print() throws IOException {
+        sb.append("  ").append(hello).append("\n");
+        sb.append("+ ").append(world).append("\n");
+        sb.append("-------\n");
+        sb.append(N / 100000 == 0 ? "  " : " ").append(N);
+        bw.write(sb.toString());
+        bw.flush();
+        bw.close();
+        br.close();
+    }
+
+}
+```