[ADD] BOJ 'no.10872' by.정재현

code/BOJ/no.10870/no.10870_정재현.java

@@ -0,0 +1,18 @@
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.io.IOException;
+
+public class Main{
+    public static void main(String[] args) throws IOException {
+
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));  
+        int n = Integer.parseInt(br.readLine());
+        int result = Fibonacci(n); 
+        System.out.println(result);
+  }  
+    public static int Fibonacci(int n){
+        if(n==0) return 0;
+        if(n==1) return 1;
+        return Fibonacci(n-1) + Fibonacci(n-2);
+    }
+}

code/BOJ/no.10872/no.10872_정재현.java

@@ -0,0 +1,20 @@
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.io.IOException;
+
+public class Main {
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int x = Integer.parseInt(br.readLine());
+
+        int sum = factorial(x);
+        System.out.println(sum);
+
+    }
+
+    public static int factorial(int x){
+        if(x<=1) return 1;
+
+        return x * factorial(x-1);
+    }
+}

code/BOJ/no.11729/no.11729_정재현.java

@@ -0,0 +1,31 @@
+import java.util.Scanner;
+
+public class Main{
+
+    public static StringBuilder sb = new StringBuilder();
+
+    public static void main(String[] args) {
+        Scanner in = new Scanner(System.in);
+        int N = in.nextInt();
+
+        sb.append((int)(Math.pow(2,N)-1)).append('\n');
+
+        Hanoi(N,1,2,3);
+        System.out.println(sb);  
+    }
+
+    public static void Hanoi(int N, int start, int mid, int end){
+        if(N==1){
+            sb.append(start + " " + end + "\n");
+            return;
+        }
+        //n-1개 start->mid
+        Hanoi(N-1, start, end, mid);
+
+        //1개 start->end
+        Hanoi(1, start, mid, end);
+
+        //n-1개 mid->end
+        Hanoi(N-1, mid, start, end);
+    }
+}

code/BOJ/no.2447/no.2447_정재현.java

@@ -0,0 +1,51 @@
+import java.util.Scanner;
+
+public class Main {
+    static char[][] arr;
+
+    public static void main(String[] args) {
+        Scanner in = new Scanner (System.in);
+        int N = in.nextInt();
+
+        arr = new char[N][N];
+
+        star(0,0,N,false);
+
+        StringBuilder sb = new StringBuilder();
+        for(int i = 0; i<N; i++) {
+            for(int j=0; j<N; j++) {
+                sb.append(arr[i][j]);
+            }
+            sb.append('\n');
+        }
+        System.out.print(sb);
+    }
+
+    static void star(int x, int y, int N, boolean blank) {
+        if(blank) {
+            for(int i = x; i<x+N; i++ ) {
+                for(int j = y; j<y+N; j++) {
+                    arr[i][j]=' ';
+                }
+            }
+            return;
+        }
+
+        if(N==1) {
+            arr[x][y]='*';
+            return;
+        }
+
+        int size = N/3;
+        int count = 0;
+        for(int i=x; i<x+N; i+=size) {
+            for(int j=y; j<y+N; j+=size) {
+                count++;
+                if(count==5) {
+                    star(i,j,size,true);
+                }
+                else { star(i,j,size,false);}
+            }
+        }
+    }
+}