75 lines
2.3 KiB
C++
75 lines
2.3 KiB
C++
#include <stdio.h>
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#include <string.h>
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#include <algorithm>
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using namespace std;
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int dp[(1<<16)+2][10][4];
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int map[17][17];
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int bit[(1<<16)+2];
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int main()
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{
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int i,j,n,cnt,k,l,m,p,a,ans;
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for (i=0;i<(1<<16);i++)
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{
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cnt=0;
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for (j=0;j<16;j++)
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{
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if ((i & (1<<j))!=0) cnt++;
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}
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bit[i]=cnt;
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}
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while(1)
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{
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scanf("%d",&n);
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if (n==0) break;
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for (i=0;i<n;i++)
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{
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for (j=0;j<n;j++)
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{
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scanf("%d",&map[i][j]);
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}
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}
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memset(dp,-1,sizeof(dp));
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ans=0;
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dp[0][0][0]=0;
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for (i=0;i<(1<<n);i++)
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{
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for (j=0;j<(1<<3);j++)
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{
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for (k=0;k<3;k++)
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{
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if (dp[i][j][k]==-1) continue;
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ans=max(ans,dp[i][j][k]);
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if (k==3) continue;
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for (l=0;l<n;l++)
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{
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if ((i & (1<<l))!=0) continue;
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p=(i | (1<<l));
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cnt=bit[p]-1;
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if (map[l][cnt]==0)
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{
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dp[p][j][k+1]=max(dp[p][j][k+1],dp[i][j][k]);
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}
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if (map[l][cnt]==1)
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{
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if (k==2) continue;
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if ((j & 4)!=0) dp[p][(j<<1) & 7][k+1]=max(dp[p][(j<<1) & 7][k+1],dp[i][j][k]+1);
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else dp[p][(j<<1) & 7][k+1]=max(dp[p][(j<<1) & 7][k+1],dp[i][j][k]);
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}
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if (map[l][cnt]==2)
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{
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if ((j & 4)!=0) dp[p][((j<<1) & 7)+1][k]=max(dp[p][((j<<1) & 7)+1][k],dp[i][j][k]+1);
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else dp[p][((j<<1) & 7)+1][k]=max(dp[p][((j<<1) & 7)+1][k],dp[i][j][k]);
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}
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if (map[l][cnt]==3)
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{
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dp[p][0][k]=max(dp[p][0][k],dp[i][j][k]+((j & 1)!=0)+((j & 2)!=0)+((j & 4)!=0)+1);
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}
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}
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}
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}
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}
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printf("%d\n",ans);
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}
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return 0;
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}
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