[JAVA]백준 - 14241.슬라임 합치기

www.acmicpc.net/problem/14241

14241번: 슬라임 합치기

 

 

 

 

 

 

 

 

 

풀이>

슬라임의 갯수를 입력받고,

입력된 슬라임의 사이즈를 서로 곱해 모두 더해주기

ex) 3
1 2 3

=> 1*2  + 1*3  + 2*3 = 11

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.StringTokenizer;

public class Main {
	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));

			String count = br.readLine();
			StringTokenizer sizeList = new StringTokenizer(br.readLine());
			br.close();
			int[] size = new int[Integer.parseInt(count)];
			
			for (int i = 0; i < size.length; i++) {
				size[i]=Integer.parseInt(sizeList.nextToken());
			}
			
			int sum=0;
			for(int i=0;i<size.length-1;i++) {
				for(int j=i+1;j<size.length;j++) {
					sum+=size[i]*size[j];
				}
			}
			
			bw.write(String.valueOf(sum));
			bw.flush();
			bw.close();
	}
}