[USACO2.1.1]The Castle城堡

Posted 2020-09-21

还以为要打很长呢。

 1 #include<cstdio>
 2 #define N 51
 3 #define repu(i,x,y) for(i=x;i<=y;i++)
 4 #define max(a,b) (a>b?a:b)
 5 int n,m,a[N][N],f[N][N],x=0,s[N*N];
 6 int dfs(int x,int y,int t) {
 7     f[x][y]=t; int i,j,k=4,s=1;
 8     if (!(a[x][y]&1) && y>1 && !f[x][y-1]) s+=dfs(x,y-1,t);
 9     if (!(a[x][y]&2) && x>1 && !f[x-1][y]) s+=dfs(x-1,y,t);
10     if (!(a[x][y]&4) && y<m && !f[x][y+1]) s+=dfs(x,y+1,t);
11     if (!(a[x][y]&8) && x<n && !f[x+1][y]) s+=dfs(x+1,y,t);
12     return s;
13 }
14 int main() {
15     int i,j,k,l,t,ans=0; scanf("%d%d",&m,&n);
16     repu(i,1,n)
17         repu(j,1,m)
18             scanf("%d",&a[i][j]);
19     repu(i,1,n)
20         repu(j,1,m)
21             if (!f[i][j]) 
22                 ++x,s[x]=dfs(i,j,x),ans=max(ans,s[x]);
23     printf("%d\n%d\n",x,ans); ans=0;
24     for (j=1;j<=m;j++)
25         for (i=n;i>=1;i--) {
26             if (f[i][j]!=f[i-1][j])
27                 if (s[f[i][j]]+s[f[i-1][j]]>ans)
28                     ans=s[f[i][j]]+s[f[i-1][j]],k=i,l=j,t=1;
29             if (f[i][j]!=f[i][j+1])
30                 if (s[f[i][j]]+s[f[i][j+1]]>ans)
31                     ans=s[f[i][j]]+s[f[i][j+1]],k=i,l=j,t=0;
32         }
33     printf("%d\n%d %d %c\n",ans,k,l,t?‘N‘:‘E‘);
34 }

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