[20251029] BOJ / G2 / 수열과 개구리 / 한종욱

Ukj0ng/202510/29 BOJ G2 수열과 개구리.md

@@ -0,0 +1,91 @@
+```
+import java.io.*;
+import java.util.*;
+
+public class Main {
+    private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    private static final BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
+    private static final long INF = Long.MAX_VALUE/2;
+    private static List<Integer>[] graph;
+    private static long[] dist;
+    private static int[] a, b;
+    private static int N;
+    public static void main(String[] args) throws IOException {
+        init();
+        dijkstra();
+        for (int i = 1; i <= N; i++) {
+            bw.write(dist[i] + " ");
+        }
+
+        bw.flush();
+        bw.close();
+        br.close();
+    }
+
+    private static void init() throws IOException {
+        N = Integer.parseInt(br.readLine());
+
+        a = new int[N+1];
+        b = new int[N+1];
+        dist = new long[N+1];
+        graph = new List[N+1];
+
+        for (int i = 1; i <= N; i++) {
+            graph[i] = new ArrayList<>();
+        }
+
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        for (int i = 1; i <= N; i++) {
+            a[i] = Integer.parseInt(st.nextToken());
+            if (1 <= i-a[i] && i-a[i] <= N) {
+                graph[i-a[i]].add(i);
+            }
+
+            if (1 <= i+a[i] && i+a[i] <= N) {
+                graph[i+a[i]].add(i);
+            }
+        }
+
+        st = new StringTokenizer(br.readLine());
+        for (int i = 1; i <= N; i++) {
+            b[i] = Integer.parseInt(st.nextToken());
+        }
+    }
+
+    private static void dijkstra() {
+        PriorityQueue<Node> pq = new PriorityQueue<>((o1, o2) -> Long.compare(o1.cost, o2.cost));
+        Arrays.fill(dist, INF);
+        for (int i = 1; i <= N; i++) {
+            if (i-a[i] < 1 || i+a[i] > N) {
+                dist[i] = b[i];
+                pq.add(new Node(i, b[i]));
+            }
+        }
+
+        while (!pq.isEmpty()) {
+            Node current = pq.poll();
+
+            if (current.cost > dist[current.dest]) continue;
+
+            for (int nDest : graph[current.dest]) {
+                long nCost = current.cost + b[nDest];
+
+                if (nCost < dist[nDest]) {
+                    dist[nDest] = nCost;
+                    pq.add(new Node(nDest, dist[nDest]));
+                }
+            }
+        }
+    }
+
+    static class Node {
+        int dest;
+        long cost;
+
+        public Node(int dest, long cost) {
+            this.dest = dest;
+            this.cost = cost;
+        }
+    }
+}
+```