A. Cirno's Perfect Bitmasks Classroom

https://codeforces.com/contest/1688/submission/159441503

Codeforces/1688/A/A.cpp

@@ -0,0 +1,32 @@
+#include <iostream>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+int t, x, y;
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> t;
+
+    while (t--) {
+        cin >> x;
+
+        int k = 0;
+        while (!((x >> k) & 1) && k <= 30) k++;
+        y = 1 << k;  // 此时满足 (x & y) > 0
+
+        if ((x ^ y) <= 0) {
+            int k = 0;
+            while (((x >> k) & 1) && k <= 30) k++;
+            y += 1 << k;  // 此时满足 (x ^ y) > 0
+        }
+
+        cout << y << endl;
+    }
+
+    return 0;
+}