有一招妙法叫做下载数据
by WanderingTrader @ 2022-07-24 22:13:43
建议参考[这个](https://www.luogu.com.cn/discuss/445321)
by ineverleft @ 2022-07-24 22:16:41
```cpp
#include <iostream>
#include <cmath>
using namespace std;
int main() {
unsigned long long n, k; cin >> n >> k;
unsigned long long l = 1, r = (1ull << (n - 1)) - 1 + (1ull << (n - 1));
if (n < 64)
r++;
int flag = 0;
while (l < r) {
unsigned long long mid = l + ((r - l) >> 1);
if (k < mid)
putchar(flag + '0'), r = mid, flag = 0;
else
putchar((flag + 1) % 2 + '0'), l = mid + 1, flag = 1;
} if (n == 64)
putchar('0');
return 0;
}
```
by RoyWu1207 @ 2022-07-25 08:40:54
终于AC了
by RoyWu1207 @ 2022-07-25 08:41:30