1001: [BeiJing2006] Wolf catch Rabbit (min cut)

Test instructions is obviously the minimum cut, according to the minimum cut maximum flow theorem, the value is equivalent to the maximum flow.

On the template.

#include <iostream>#include<cstdio>#include<cstring>using namespacestd;Const intMAXN =1000010;//maximum number of pointsConst intMAXM =6000060;//maximum number of edgesConst intINF =0x3f3f3f3f;structdinic{intN, M, T, E, FIRST[MAXN], NEXT[MAXM], U[MAXM], V[MAXM], FLOW[MAXM]; intQ[MAXN], D[MAXN], WORK[MAXN], S[MAXN]; voidAddintAintBintf) {U[e]=A; V[e]=b; Flow[e]=F; Next[e]=First[a]; First[a]=e; E++; }    voidInitintNintm) { This->n=N;  This->m=m; T= n * M-1; E=0;  for(i =0; I <= T; i + +) First[i]= -1; }    intBFs () {intI, j, rear;  for(i =1; I <= T; i + +) D[i]= -1; d[0] =0; Rear=0; Q[rear++] =0;  for(i =0; I < rear; i + +)             for(j = First[q[i]]; J! =-1; j =Next[j])if(Flow[j] && d[v[j]] = =-1) {D[v[j]]= D[q[i]] +1; if(V[j] = =T)return 1; Q[rear++] =V[j]; }        return 0; }    intDinic () {intI, J, cur, r, res =0;  while(BFS ()) {R=0; Cur=0;  for(i =0; I <= T; i + +) Work[i]=First[i];  for(;;) {                if(cur = =T) {intA = INF, Minr =R;  for(i =0; I < R; i + +)                        if(Flow[s[i]) <a) {a=Flow[s[i]]; Minr=i; }                     for(i =0; I < R; i + +) {Flow[s[i]]-=A; Flow[s[i]^1] +=A; } R=Minr; Cur=U[s[r]]; Res+=A; }                 for(i = work[cur]; I! =-1; i =Next[i])if(Flow[i] && d[v[i]] = = D[cur] +1)                         Break; Work[cur]=i; if(I! =-1) {S[r++] =i; Cur=V[i]; }                Else{D[cur]= -1; if(r = =0)                         Break; R--; Cur=U[s[r]]; }            }        }        returnRes; }};D inic dinic;intMain () {intn,m;  while(SCANF ("%d%d", &n, &m) = =2) {dinic.init (n,m); intx;  for(intI=0; i<n; ++i) { for(intj=0; j<m-1; ++j) {scanf ("%d",&x); Dinic.add (i*m+j,i*m+j+1, x); Dinic.add (i*m+j+1, i*m+j,x); }            }             for(intI=0; i<n-1; ++i) { for(intj=0; j<m; ++j) {scanf ("%d",&x); Dinic.add (i*m+j, (i+1) *m+j,x); Dinic.add ((i+1) *m+j,i*m+j,x); }            }             for(intI=0; i<n-1; ++i) { for(intj=0; j<m-1; ++j) {scanf ("%d",&x); Dinic.add (i*m+j, (i+1) *m+j+1, x); Dinic.add ((i+1) *m+j+1, i*m+j,x); }} printf ("%d\n", Dinic.dinic ()); }    return 0;}

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1001: [BeiJing2006] Wolf catch Rabbit (min cut)