1 #include<cstdio> 2 #include<iostream> 3 #include<cstring> 4 #define M 100009 5 #define inf 2139062143 6 using namespace std; 7 int n,a1,a2,an,b1,b2,bn,tot,cnt=1,T,ans,head[M],d[M],q[2*M],next[10*M],u[10*M],v[10*M]; 8 char ch[60][60]; 9 bool bfs() 10 { 11 memset(d,0,sizeof(int)*(T+1)); 12 int h=0,t=1; 13 q[1]=0; 14 d[0]=1; 15 for(;h<t;) 16 { 17 h++; 18 int p=q[h]; 19 for(int i=head[p];i;i=next[i]) 20 if(!d[u[i]]&&v[i]) 21 { 22 d[u[i]]=d[p]+1; 23 if(d[T]) 24 return 1; 25 t++; 26 q[t]=u[i]; 27 } 28 } 29 return 0; 30 } 31 int dinic(int s,int f) 32 { 33 if(s==T) 34 return f; 35 int rest=f; 36 for(int i=head[s];i&&rest;i=next[i]) 37 if(v[i]&&d[u[i]]==d[s]+1) 38 { 39 int now=dinic(u[i],min(rest,v[i])); 40 if(!now) 41 d[u[i]]=0; 42 v[i]-=now; 43 v[i^1]+=now; 44 rest-=now; 45 } 46 return f-rest; 47 } 48 void jia1(int a1,int a2,int a3) 49 { 50 cnt++; 51 next[cnt]=head[a1]; 52 head[a1]=cnt; 53 u[cnt]=a2; 54 v[cnt]=a3; 55 return; 56 } 57 void jia(int a1,int a2,int a3) 58 { 59 jia1(a1,a2,a3); 60 jia1(a2,a1,0); 61 return; 62 } 63 void build(int a1,int a2,int an,int b1,int b2,int bn) 64 { 65 T=n+1; 66 cnt=1; 67 memset(head,0,sizeof(int)*(T+1)); 68 jia(0,a1,2*an); 69 jia(a2,T,2*an); 70 jia(0,b1,2*bn); 71 jia(b2,T,2*bn); 72 for(int i=1;i<=n;i++) 73 for(int j=1;j<=n;j++) 74 { 75 if(ch[i][j]=='O') 76 jia(i,j,2); 77 if(ch[i][j]=='N') 78 jia(i,j,inf); 79 } 80 return; 81 } 82 int main() 83 { 84 for(;scanf("%d%d%d%d%d%d%d",&n,&a1,&a2,&an,&b1,&b2,&bn)==7;) 85 { 86 a1++; 87 a2++; 88 b1++; 89 b2++; 90 for(int i=1;i<=n;i++) 91 scanf("%s",ch[i]+1); 92 build(a1,a2,an,b1,b2,bn); 93 ans=0; 94 for(;bfs();) 95 ans+=dinic(0,inf); 96 if(ans==2*an+2*bn) 97 { 98 build(a1,a2,an,b2,b1,bn); 99 ans=0; 100 for(;bfs();) 101 ans+=dinic(0,inf); 102 if(ans==2*an+2*bn) 103 printf("Yes\n"); 104 else 105 printf("No\n"); 106 } 107 else 108 printf("No\n");} 109 return 0; 110 }
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