"Bzoj 1087" [SCOI2005] non-aggression king

Description

Put K Kings in NxN's chessboard, so that they do not attack each other, there are many kinds of layout plan. The king can attack it up and down, as well as the left upper left lower right up to the bottom right in the next eight directions in the vicinity of a grid, a total of 8 squares.

Input

Only one row, containing two numbers n,k (1 <=n <=9, 0 <= K <= n * N)

Output

Number of scenarios.

Sample Input3 2Sample Output -The classmate had already played the watch before, Orzthe positive solution pressure Dp,f[i][s][k] indicates that the state of the line on the first row is S, with K selectedpre-processing all the possible states, DP.

1#include <cstdio>2#include <cstring>3 #definell Long Long4 using namespacestd;5 intgs[520],a[520][ One];6 BOOLpd[520];7 intn,k;8ll ans,f[ One][520][ -];9 BOOLOkintXinty) {Ten      for(intI=1; i<=9; i++)if(a[x][i]&& (a[y][i]| | a[y][i-1]|| a[y][i+1]))return 0; One     return 1; A } -   - intMain () { thescanf"%d%d",&n,&K); -memset (PD,1,sizeof(PD)); -      for(intI=1; I<= (1<<n)-1; i++){ -         intTmp=i,cnt=0; +          while(TMP) { -a[i][++cnt]=tmp&1; gs[i]+=1&tmp; +tmp>>=1; A         } at          for(intj=1; j<=n;j++)if(a[i][j]==1&&a[i][j+1]==1){ -pd[i]=0; Break; -         } -         if(Pd[i]) f[1][i][gs[i]]+=1; -     } -f[1][0][0]=1; in      for(intI=2; i<=n;i++) -          for(intj=0; J<= (1<<n)-1; j + +){ to             if(!pd[j])Continue; +              for(intk=0; K<= (1<<n)-1; k++){ -                 if(OK (j,k)) { the                      for(intl=gs[k];l<=k;l++) *f[i][k][l]+=f[i-1][j][l-Gs[k]]; $                 }Panax Notoginseng             } -         } the      for(intI=0; I<= (1<<n)-1; i++)if(Pd[i]) ans+=F[n][i][k]; +printf"%lld", ans); A}

"Bzoj 1087" [SCOI2005] non-aggression king