[BOJ] 백준 2003 수들의 합 2

 

[문제]

https://www.acmicpc.net/problem/2003

 

 

[소스 코드]

import java.io.*;
import java.util.*;

public class Main {
	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st = new StringTokenizer(br.readLine());
		int n = Integer.parseInt(st.nextToken());
		int m = Integer.parseInt(st.nextToken());
		int[] nums = new int[n+1];
		st = new StringTokenizer(br.readLine());
		for(int i=0;i<n;i++) {
			nums[i] = Integer.parseInt(st.nextToken());
		}
		int cnt = 0;
		int start = 0;
		int end = 1;
		if(nums[start]==m) cnt++;
		int sum = nums[start] + nums[end];
		while(end<n) {
			if(sum<=m) {
				if(sum==m) cnt++;
				sum += nums[++end];
			}
			else {
				sum -= nums[start++];
			}
		}
		System.out.println(cnt);
	}
}