[20251204] BOJ / G4 / 수들의 합 4 / 강신지

ksinji/202512/04 BOJ 수들의 합 4.md

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+```java
+import java.io.*;
+import java.util.*;
+
+public class Main {
+    public static void main(String[] args) throws Exception {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+
+        int n = Integer.parseInt(st.nextToken());
+        int k = Integer.parseInt(st.nextToken());
+
+        st = new StringTokenizer(br.readLine());
+
+        long sum = 0L;
+        long answer = 0L;
+
+        Map<Long, Long> count = new HashMap<>();
+        count.put(0L, 1L);
+
+        for (int i = 0; i < n; i++) {
+            int x = Integer.parseInt(st.nextToken());
+            sum += x;
+
+            long target = sum - k;
+            if (count.containsKey(target)) {
+                answer += count.get(target);
+            }
+
+            count.put(sum, count.getOrDefault(sum, 0L) + 1);
+        }
+
+        System.out.println(answer);
+    }
+}
+```