[国家集训队2011]happiness(吴确) (最小割)

  1 #include<queue>
  2 #include<cstdio>
  3 #include<iostream>
  4 #define MAXN 200010
  5 
  6 using namespace std;
  7 
  8 const int INF=0x7fffffff;
  9 
 10 struct node {
 11     int to;
 12     int next;
 13     int val;
 14 };
 15 node e[MAXN];
 16 
 17 int head[MAXN],cur[MAXN],tot=1;
 18 
 19 int depth[MAXN],ans,map[2][110][110],src,decc,p,sum;
 20 
 21 int n,m;
 22 
 23 queue<int> q;
 24 
 25 inline void read(int&x) {
 26     int f=1;x=0;char c=getchar();
 27     while(c>‘9‘||c<‘0‘) {if(c==‘-‘) f=-1;c=getchar();}
 28     while(c>=‘0‘&&c<=‘9‘) {x=(x<<1)+(x<<3)+c-48;c=getchar();}
 29     x=x*f;
 30 }
 31 
 32 inline int cal(int i,int j) {
 33     return (i-1)*m+j;
 34 }
 35 
 36 inline void add(int x,int y,int z) {
 37     e[++tot].to=y;
 38     e[tot].val=z;
 39     e[tot].next=head[x];
 40     head[x]=tot;
 41 }
 42 
 43 inline void add_edge(int x,int y,int z,int f) {
 44     if(!f) {
 45         add(x,y,z);
 46         add(y,x,0);
 47     }
 48     else {
 49         add(x,y,z);
 50         add(y,x,z);
 51     }
 52 }
 53 
 54 bool bfs() {
 55     for(int i=0;i<=decc;i++) cur[i]=head[i],depth[i]=-1;
 56     while(!q.empty()) q.pop();
 57     q.push(src);
 58     depth[src]=0;
 59     while(!q.empty()) {
 60         int u=q.front();
 61         q.pop();
 62         for(int i=head[u];i!=-1;i=e[i].next) {
 63             int to=e[i].to;
 64             if(e[i].val&&depth[to]==-1) {
 65                 q.push(to);
 66                 depth[to]=depth[u]+1;
 67                 if(to==decc) return true;  //卧槽 连return都忘了 只剩一个true 找了好长时间的错 
 68             }
 69         }
 70     }
 71     return false;
 72 }
 73 
 74 int dfs(int now,int flow) {
 75     if(now==decc) return flow;
 76     int rest=0,delat;
 77     for(int & i=cur[now];i!=-1;i=e[i].next) {
 78         int to=e[i].to;
 79         if(e[i].val&&depth[to]==depth[now]+1) {
 80             delat=flow-rest;
 81             delat=dfs(to,min(e[i].val,delat));
 82             e[i].val-=delat;
 83             e[i^1].val+=delat;
 84             rest+=delat;
 85             if(rest==flow) return flow;
 86         }
 87     }
 88     if(!rest) depth[now]=-1;
 89     return rest;
 90 }
 91 
 92 inline void dinic() {
 93     while(bfs())
 94       ans+=dfs(src,INF);
 95     return;
 96 }
 97 
 98 inline int hhh(){
 99     freopen("nt2011_happiness.in","r",stdin);
100     freopen("nt2011_happiness.out","w",stdout); 
101     read(n);read(m);
102     fill(head,head+1+MAXN,-1);
103     src=0;decc=n*m+1;
104     for(int i=1;i<=n;i++) for(int j=1;j<=m;j++) read(map[0][i][j]),sum+=map[0][i][j],map[0][i][j]<<=1;
105     for(int i=1;i<=n;i++) for(int j=1;j<=m;j++) read(map[1][i][j]),sum+=map[1][i][j],map[1][i][j]<<=1;
106     for(int i=1;i<n;i++)  
107       for(int j=1;j<=m;j++) {
108         read(p);
109         map[0][i][j]+=p;map[0][i+1][j]+=p;
110         sum+=p;
111         add_edge(cal(i,j),cal(i+1,j),p,1);
112       }
113     for(int i=1;i<n;i++)  
114       for(int j=1;j<=m;j++) {
115         read(p);
116         map[1][i][j]+=p;map[1][i+1][j]+=p;
117         sum+=p;
118         add_edge(cal(i,j),cal(i+1,j),p,1);
119       }
120     for(int i=1;i<=n;i++) 
121       for(int j=1;j<m;j++) {
122           read(p);
123         map[0][i][j]+=p;map[0][i][j+1]+=p;
124         sum+=p;
125         add_edge(cal(i,j),cal(i,j+1),p,1);
126       }
127     for(int i=1;i<=n;i++) 
128       for(int j=1;j<m;j++) {
129           read(p);
130         map[1][i][j]+=p;map[1][i][j+1]+=p;
131         sum+=p;
132         add_edge(cal(i,j),cal(i,j+1),p,1);
133       }
134     for(int i=1;i<=n;i++) 
135       for(int j=1;j<=m;j++) 
136         add_edge(src,cal(i,j),map[0][i][j],0),
137         add_edge(cal(i,j),decc,map[1][i][j],0);
138     
139     dinic();
140     printf("%d\n",sum-(ans>>1));
141     return 0;
142 } 
143 
144 int sb=hhh();
145 int main() {;}