링크 → https://www.acmicpc.net/problem/10819

• 아영

  • 코드

  package Baekjoon.java.silver;
  
  import java.io.BufferedReader;
  import java.io.InputStreamReader;
  import java.util.Arrays;
  import java.util.StringTokenizer;
  
  public class boj10819 {
      static int max,N,nums[];
      public static void main(String[] args) throws Exception{
          BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
          N = Integer.parseInt(br.readLine());
          max = -10000;
          nums = new int[N];
          StringTokenizer st = new StringTokenizer(br.readLine());
          for (int i = 0; i < N; i++) {
              nums[i] = Integer.parseInt(st.nextToken());
          }
          boolean[] checked = new boolean[N];
          int[] ordered = new int[N];
          dfs(0,checked,ordered);
          System.out.println(max);
  
      }
  
      private static void dfs(int idx, boolean[] checked,int[] ordered){
         if(idx==N){
             int prev = ordered[0];
             int result = 0;
             for (int i = 1; i < N; i++) {
                 result += Math.abs(nums[prev]-nums[ordered[i]]);
                 prev = ordered[i];
             }
             if(max<result) max = result;
         }
  
          for (int i = 0; i < N; i++) {
              if(checked[i]) continue;
              checked[i] = true;
              ordered[idx] = i;
              dfs(idx+1,checked,ordered);
              checked[i] = false;
          }
      }
  }
  

  • 시간,메모리

  

• 은영

  • 코드

  
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.util.StringTokenizer;
  
  public class baekjoon10819 {
  
  	static int N,ans=0;
  	static int[] arr, num;
  	static boolean visit[];
  	public static void main(String[] args) throws NumberFormatException, IOException {
  		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  		StringTokenizer st;
  		
  		N = Integer.parseInt(br.readLine());
  		arr = new int[N];
  		num = new int[N];
  		visit = new boolean[N];
  		
  		st = new StringTokenizer(br.readLine()+" ");
  		for (int i = 0; i < N; i++) {
  			arr[i] = Integer.parseInt(st.nextToken());
  		}
  		
  		func(0);
  		System.out.println(ans);
  
  	}
  	private static void func(int cnt) {
  		if(cnt==N)
  		{
  			int sum=0;
  			for (int i = 0; i < N-1; i++) {
  				sum+= Math.abs(num[i]-num[i+1]);
  			}
  			ans = Math.max(ans, sum);
  			return;
  		}
  		for (int i = 0; i < N; i++) {
  			if(!visit[i]) {
  				visit[i] = true;
  				num[cnt] = arr[i];
  				func(cnt+1);
  				visit[i] = false;
  			}
  		}
  		
  		
  	}
  
  }
  

  • 시간,메모리

  

• 건

  • 코드

  package day_0524;
  
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.util.StringTokenizer;
  
  public class BOJ10819 {
  	
  	static int n;
  	static int[] arr;
  	static int[] isSelected;
  	static boolean[] isVisited;
  	static int answer;
  	
  	public static void main(String[] args) throws IOException{
  		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  		StringTokenizer stk;
  		
  		n = Integer.parseInt(br.readLine());
  		
  		stk = new StringTokenizer(br.readLine());
  		
  		arr = new int[n];
  		for (int i = 0; i < n; i++) {
  			arr[i] = Integer.parseInt(stk.nextToken());
  		}
  		
  		isSelected = new int[n];
  		isVisited = new boolean[n];
  		
  		permu(0);
  		
  		System.out.println(answer);
  	}
  	
  	static void permu(int cnt) {
  		if (cnt == n) {
  			int tAnswer = 0;
  			tAnswer = calc();
  			if (tAnswer >= answer) {
  				answer = tAnswer;
  			}
  			return;
  		}
  		
  		for (int i = 0; i < n; i++) {
  			if(!isVisited[i]) {
  				isSelected[cnt] = arr[i];
  				isVisited[i] = true;
  				permu(cnt + 1);
  				isVisited[i] = false;
  			}
  		}
  	}
  	
  	static int calc() {
  		int result = 0;
  		for (int i = 0; i < n - 1; i++) {
  			result += Math.abs(isSelected[i] - isSelected[i+1]);
  		}
  		
  		return result;
  	}
  
  }
  

  • 시간,메모리

  

• 용문

  • 코드

  class BJ10819 {
      
      private var N: Int = 0
      private var nums: [Int] = []
      private var selectedNums: [Int] = []
      private var selected: [Bool] = []
      private var before: Int = 0
      private var answer: Int = 0
      
      func solve() {
          readComponents()
          calc()
          printAnswer()
      }
      
      private func readComponents() {
          self.N = Int( readLine()! )!
          self.nums = readLine()!.split(separator: " ").map({ Int($0)! })
          self.selected = .init(repeating: false, count: N)
          self.selectedNums = .init(repeating: 0, count: N)
      }
      
      private func calc() {
          calcFrom(count: 0)
      }
      
      private func calcFrom(count: Int) {
          if count == N {
              var value = 0
              
              for index in selectedNums.indices {
                  if index == N - 1 { break }
                  value += abs(selectedNums[index] - selectedNums[index + 1])
              }
                          
              answer = max(answer, value)
              
              return
          }
          
          for index in 0..<N {
              if selected[index] { continue }
              selected[index] = true
              selectedNums[count] = nums[index]
              calcFrom(count: count + 1)
              selected[index] = false
          }
      }
      
      private func printAnswer() {
          print(answer)
      }
  }
  
  BJ10819().solve()
  

  • 시간,메모리