new file: P17088.cpp

P17088.cpp

@@ -0,0 +1,25 @@
+#include <bits/stdc++.h>
+#define int long long
+using namespace std;
+int n;
+signed main()
+{
+    scanf("%lld", &n);
+    int ans = 0;
+    for (int i = 0; i < n / 2; ++i)
+    {
+        ans <<= 1;
+        ans += 1;
+    }
+    for (int i = 0; i < n / 2; ++i)
+    {
+        ans <<= 1;
+    }
+    printf("%lld\n", ans);
+    return 0;
+}
+/*
+5
+00000
+末尾0的个数等于1的个数
+*/