[20250926] BOJ / G4 / 작업 / 이강현

lkhyun/202509/26 BOJ G4 작업.md

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+```java
+import java.util.*;
+import java.io.*;
+
+public class Main{
+    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    static BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
+    static StringTokenizer st;
+    static StringBuilder sb = new StringBuilder();
+    static int N;
+    static List<Integer>[] prevTask;
+    static int[] prevCnt;
+    static int[] cost;
+    static int ans = 0;
+
+    public static void main(String[] args) throws Exception {
+        N = Integer.parseInt(br.readLine());
+        prevTask = new List[N+1];
+        for (int i = 1; i <= N; i++) {
+            prevTask[i] = new ArrayList<>();
+        }
+        prevCnt = new int[N+1];
+        cost = new int[N+1];
+
+        for (int i = 1; i <= N; i++) {
+            st = new StringTokenizer(br.readLine());
+            cost[i] = Integer.parseInt(st.nextToken());
+            int tmp = Integer.parseInt(st.nextToken());
+            for (int j = 0; j < tmp; j++) {
+                prevTask[Integer.parseInt(st.nextToken())].add(i);
+                prevCnt[i]++;
+            }
+        }
+        solve();
+        bw.write(ans+"");
+        bw.close();
+    }
+    public static void solve(){
+        PriorityQueue<int[]> q = new PriorityQueue<>((a,b) -> Integer.compare(a[1],b[1]));
+        boolean[] visited = new boolean[N+1];
+        for (int i = 1; i <= N; i++) {
+            if(prevCnt[i] == 0){
+                q.offer(new int[]{i,cost[i]});
+                visited[i] = true;
+            }
+        }
+
+        while(!q.isEmpty()){
+            int[] cur = q.poll();
+            ans = Math.max(ans,cur[1]);
+
+            for (int next : prevTask[cur[0]]) {
+                if(!visited[next]){
+                    prevCnt[next]--;
+                    if(prevCnt[next] == 0){
+                        q.offer(new int[]{next,cur[1]+cost[next]});
+                        visited[next] = true;
+                    }
+                }
+            }
+        }
+    }
+}
+```