diff --git a/src/week3/BOJ12851/BOJ12851_V1.cpp b/src/week3/BOJ12851/BOJ12851_V1.cpp
new file mode 100644
index 0000000..482e5b8
--- /dev/null
+++ b/src/week3/BOJ12851/BOJ12851_V1.cpp
@@ -0,0 +1,43 @@
+#include <bits/stdc++.h>
+using namespace std;
+int brother, subin;
+int ret = INT_MAX;
+int ret_cnt;
+int visited[100001];
+void solve(int idx, int level) {
+    if (idx > 100000 || idx < 0) {
+        return;
+    }
+    if (visited[idx]) return;
+    if (level > ret) return;
+    if (level == ret && idx == brother) {
+        ret_cnt++;
+        return;
+    }
+    if (idx == brother && level < ret) {
+        ret = level;
+        ret_cnt = 1;
+        return;
+    }
+    
+    visited[idx] = 1;
+    solve(idx-1, level+1);
+    solve(idx+1, level+1);
+    solve(idx*2, level+1);
+    visited[idx] = 0;
+}
+int main() {
+
+    ios::sync_with_stdio(false);
+    cin.tie(NULL);
+    cout.tie(NULL);
+
+    cin >> subin >> brother;
+
+    solve(subin, 0);
+
+    cout << ret << '\n' << ret_cnt << '\n';
+
+
+    return 0;
+}
\ No newline at end of file
diff --git a/src/week3/BOJ12851/BOJ12851_V2.cpp b/src/week3/BOJ12851/BOJ12851_V2.cpp
new file mode 100644
index 0000000..9cb21e3
--- /dev/null
+++ b/src/week3/BOJ12851/BOJ12851_V2.cpp
@@ -0,0 +1,38 @@
+#include <bits/stdc++.h>
+using namespace std;
+int brother, subin;
+int visited[100001];
+int cnt[100001];
+int main() {
+
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+    cout.tie(NULL);
+
+    cin >> subin >> brother;
+    queue<int> q;
+    q.push(subin);
+    visited[subin] = 1;
+    cnt[subin] = 1;
+    int now;
+    while(!q.empty()) {
+        now = q.front();
+        q.pop();
+        for (int next : {now-1, now+1, now *2}) {
+            if (0 <= next && next <= 100000) {
+                if (visited[next] == 0) {
+                    q.push(next);
+                    visited[next] = visited[now] + 1;
+                    cnt[next] = cnt[now];
+                } else if (visited[next] == visited[now] + 1) {
+                    cnt[next] += cnt[now];
+                }
+
+            }
+        }
+
+    }
+
+    cout << visited[brother]-1 << '\n' << cnt[brother] << '\n';
+    return 0;
+}
\ No newline at end of file