https://ac.nowcoder.com/acm/contest/889/D

#include
      
       using namespace std;//__#define pb push_backtypedef long long ll;typedef unsigned long long ull;struct node{    int num;    ull sum;}a[1<<19],b[1<<19];bool cmp(node p,node q){    return p.sum
       
        s&&r)            r--;        if(a[l].sum+b[r].sum==s)            break;        l++;    }    for(int i=0;i<(int)n/2;i++)        printf("%d",(a[l].num>>i)&1);    for(int i=int(n/2);i
        
         >i)&1);    return 0;}