12852 1로 만들기 2 / 다이나믹 프로그래밍, 그래프

2021_05/BJ_12852.cpp

@@ -0,0 +1,44 @@
+#include <iostream>
+#include <queue>
+#include <vector>
+#include <algorithm> 
+using namespace std;
+
+int main()
+{
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+
+    int n;
+    cin >> n;
+
+    vector<int> res(n + 1);
+    vector<int> track(n + 1);
+
+    for (int i = 2; i <= n; i++) {
+        res[i] = res[i - 1] + 1;
+        track[i] = i - 1;
+
+        if (i % 2 == 0 && res[i] > res[i / 2] + 1) {
+            res[i] = res[i / 2] + 1;
+            track[i] = i / 2;
+
+        }
+
+        if (i % 3 == 0 && res[i] > res[i / 3] + 1) {
+            res[i] = res[i / 3] + 1;
+            track[i] = i / 3;
+        }
+    }
+
+    cout << res[n] << endl;
+
+    cout << n << " ";
+    while (n != 1) {
+        cout << track[n] << " ";
+        n = track[n];
+    }
+
+
+    return 0;
+}