diff --git a/19xxx/19946.cpp b/19xxx/19946.cpp
new file mode 100644
index 00000000..757c6146
--- /dev/null
+++ b/19xxx/19946.cpp
@@ -0,0 +1,21 @@
+#include <iostream>
+using namespace std;
+
+void solve(void) {
+  unsigned long long n; cin >> n;
+
+  int ans = 64;
+  while (!(n & 1)) {
+    n >>= 1;
+    ans--;
+  }
+  cout << ans;
+}
+
+int main(void) {
+  ios::sync_with_stdio(false);
+  cin.tie(nullptr); cout.tie(nullptr);
+
+  solve();
+  return 0;
+}
\ No newline at end of file