24-03-15 숨바꼭질 3

yuyu0830/탐색/12851.cpp

@@ -0,0 +1,83 @@
+// BFS 골드 4 숨바꼭질 2 https://www.acmicpc.net/problem/12851
+#include <iostream>
+#include <vector>
+#include <queue>
+
+using namespace std;
+
+typedef pair<int, int> ii;
+
+int n, k;
+int dist[100001] = {0, };
+bool visited[100001] = {0, };
+
+void solve() {
+    priority_queue<int, vector<int>, greater<int>> q[2];
+    vector<int> visitedVec;
+
+    bool e = false;
+
+    q[e].push(n);
+    dist[n] = 1;
+    visited[n] = 1;
+
+    int time = 1, cnt = 0;
+
+    if (n == k) {
+        printf("0\n1");
+        return;
+    }
+
+    while (true) {
+        while (!q[e].empty()) {
+            int cur = q[e].top();
+
+            q[e].pop();
+
+            for (int i : {cur - 1, cur * 2, cur + 1}) {
+                if (i < 0 || i > 100000) continue;
+
+                if (i == k) cnt += dist[cur] + 1;
+
+                if (!dist[i]) {
+                    q[!e].push(i);
+                    visitedVec.push_back(i);
+                }
+
+                if (!visited[i]) 
+                    dist[i] += dist[cur];
+
+                if (cur > k) break;
+            }
+
+            if (cur > k) {
+                q[e] = priority_queue <int, vector<int>, greater<int>> ();
+                break;
+            }
+        }
+
+        if (cnt) {
+            printf("%d\n%d", time, dist[k]);
+            break;
+        }
+
+        while (!visitedVec.empty()) {
+            int v = visitedVec.back();
+            visitedVec.pop_back();
+
+            visited[v] = 1;
+        }
+
+        e = !e;
+        time++;
+    }
+}
+
+int main() {
+    cin >> n >> k;
+    solve();
+
+    // for (int i = 0; i < 20; i++) {
+    //     printf("%d : %d\n", i, dist[i]);
+    // }
+}