package practice2_hashing;

import java.util.*;

public class Question4 {

// 음수가 있는 부분 수열.. 진짜 개어렵네..?

public int solution(int[] nums, int m){

int answer = 0;

HashMap<Integer, Integer> nH = new HashMap<>();

int sum = 0;

nH.put(0, 1);

for(int x : nums){

sum += x;

if(nH.containsKey(sum-m)) answer += nH.get(sum-m);

nH.put(sum, nH.getOrDefault(sum, 0) + 1);

}

return answer;

}

public static void main(String[] args){

Question4 T = new Question4();

System.out.println(T.solution(new int[]{2, 2, 3, -1, -1, -1, 3, 1, 1}, 5));

System.out.println(T.solution(new int[]{1, 2, 3, -3, 1, 2, 2, -3}, 5));

System.out.println(T.solution(new int[]{1, 2, 3, -3, 1, 2}, 3));

System.out.println(T.solution(new int[]{-1, 0, 1}, 0));

System.out.println(T.solution(new int[]{-1, -1, -1, 1}, 0));

}

}