【bitset】Kth Minimum Clique

 #include<bits/stdc++.h>
 #define B bitset<105>
 using namespace std;
 typedef long long ll ;
 const int N =  ;
 B G[N] ;
 ll a[N] ;
 typedef struct Node {
     B mask;
     ll val;
     Node() {}
     Node( B b,ll v):mask(b),val(v){}
     bool operator < (const Node & rhs )const {
         return val > rhs.val ;
     }
 }Node ;
 int main()
 {
     int n,k;
     while(~scanf("%d%d",&n,&k)){
         for(int i=;i<=n;i++){
             scanf("%lld",&a[i]);
         }
         for(int i=;i<=n;i++){
             G[i].reset();
             for(int j=,x;j<=n;j++){
                 scanf("%1d",&x);
                 G[i][j] = x ;
             }
         }
         priority_queue < Node > Q ;
         B tmp ;
         tmp.reset();
         Q.push( Node(tmp,) );
         while( !Q.empty() ){
             Node cur = Q.top() ;
             Q.pop();
             if( !(--k) ){
                 return *printf("%lld\n",cur.val );
             }
             int pos =  ;
             for(int i=;i<=n;i++){
                 if(cur.mask[i]){
                     pos = i+ ;
                 }
             }
             for(int i=pos;i<=n;i++){
                 if( ( G[i] & cur.mask ) == cur.mask ){
                     cur.mask[i] =  ;
                     Q.push( Node(cur.mask,cur.val +a[i]) );
                     cur.mask[i] =  ;
                 }
             }
         }
         puts("-1");
     }
     return ;
 }