[Week3] BOJ 6603: 로또

[Week3] BOJ 6603: 로또

Author: sukangpunch

weekly/week03/BOJ_6603_로또/sukanpunch.java

@@ -0,0 +1,54 @@
+package stduy.week03;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.List;
+
+// 로또
+public class BOJ_6603 {
+
+    static StringBuilder sb = new StringBuilder();
+    static List<Integer> list;
+    static int[] arr;
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+        while (true) {
+            String[] s = br.readLine().split(" ");
+            int K = Integer.parseInt(s[0]);
+            if (K == 0) {
+                break;
+            }
+            arr = new int[K];
+            list = new ArrayList<>();
+
+            for (int i = 0; i < K; i++) {
+                arr[i] = Integer.parseInt(s[i + 1]);
+            }
+
+            backtrack(0, 0, K);
+            sb.append("\n");
+        }
+
+        System.out.println(sb);
+    }
+
+    private static void backtrack(int depth, int start, int K) {
+        if (depth == 6) {
+            for (int i = 0; i < 6; i++) {
+                sb.append(list.get(i)).append(" ");
+            }
+            sb.append("\n");
+            return;
+        }
+
+        for (int i = start; i < K; i++) {
+            list.add(arr[i]);
+            backtrack(depth + 1, i + 1, K);
+            list.remove(list.size() - 1);
+        }
+    }
+}