[Permutation] baekjoon-5568

Author: Seogeurim

README.md

@@ -74,6 +74,12 @@
 | 03  |     | [Baekjoon-1010 다리 놓기](https://github.com/Seogeurim/Algorithm-practice/blob/master/src/Combination/P1010) | DP     |
 | 04  | ⭐️ | [Baekjoon-1256 사전](https://github.com/Seogeurim/Algorithm-practice/blob/master/src/Combination/P1256) |        |
 
+### Permutation
+
+|  #  |   ☆    | Problem                                                                                                             | Note                      |
+| :-: | :----: | :------------------------------------------------------------------------------------------------------------------ | :------------------------ |
+| 01  |     | [Baekjoon-5568 카드 놓기](https://github.com/Seogeurim/Algorithm-practice/blob/master/src/Permutation/P5568) |      |
+
 ### Probability
 
 |  #  |   ☆    | Problem                                                                                                             | Note                      |

src/Permutation/P5568/Main.java

@@ -0,0 +1,70 @@
+package Permutation.P5568;
+
+import java.io.BufferedReader;
+import java.io.FileInputStream;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+public class Main {
+
+    static int N, K;
+    static int[] nums;
+    static int[] cases = new int[4];
+    static boolean[] visited = new boolean[10];
+    static List<Integer> ans = new ArrayList<>();
+
+    public static void main(String[] args) throws Exception {
+        System.setIn(new FileInputStream("src/Permutation/P5568/input.txt"));
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+        N = Integer.parseInt(br.readLine());
+        K = Integer.parseInt(br.readLine());
+
+        nums = new int[N];
+        for (int i = 0; i < N; i++) {
+            nums[i] = Integer.parseInt(br.readLine());
+        }
+
+        Arrays.sort(nums);
+        dfs(0);
+
+        Collections.sort(ans);
+        int count = 1;
+        for (int i = 1; i < ans.size(); i++) {
+            if (!ans.get(i).equals(ans.get(i - 1))){
+                count ++;
+            }
+        }
+
+        System.out.println(count);
+
+        br.close();
+    }
+
+    static void dfs(int count){
+        if (count == K) {
+            ans.add(arrToNum(cases, K));
+            return;
+        }
+        int selected = 0;
+        for (int i = 0; i < N; i++) {
+            if (!visited[i] && nums[i] != selected) {
+                visited[i] = true;
+                cases[count] = nums[i];
+                dfs(count + 1);
+                visited[i] = false;
+            }
+        }
+    }
+
+    static int arrToNum(int[] arr, int size){
+        StringBuilder sb = new StringBuilder();
+        for (int i = 0; i < size; i++) {
+            sb.append(arr[i]);
+        }
+        return Integer.parseInt(String.valueOf(sb));
+    }
+}

src/Permutation/P5568/input.txt

@@ -0,0 +1,6 @@
+4
+2
+1
+2
+12
+1