HDU 4888 Redraw Beautiful drawings (maximum flow, sentence ring)

http://acm.hdu.edu.cn/showproblem.php?pid=4888

Add a source point and a sink point, and build the following example :

1.   Span style= "LINE-HEIGHT:22PX; font-size:11pt; Font-family: Italic "> source point   Span style= "LINE-HEIGHT:22PX; font-size:11pt; font-family: ">->" in italics;   Span style= "LINE-HEIGHT:22PX; font-size:11pt; Font-family: Italic "> The corresponding point in each row, the traffic is limited to the line and the

2. the corresponding points in each line  - Each column corresponds to a point where the traffic is limited to K

3.   Span style= "LINE-HEIGHT:22PX; font-size:11pt; Font-family: Italic "> corresponding point of each column   Span style= "LINE-HEIGHT:22PX; font-size:11pt; font-family: ">->" in italics;   Span style= "LINE-HEIGHT:22PX; font-size:11pt; Font-family: Italic "> meeting point, flow limit for this column and

To find the maximum flow, if the maximum flow is equal to the sum of the matrix, it shows that there is a solution, otherwise there is no solution. The inferred unique solution is to infer whether there is a ring with a length greater than 2 in the residual network. If there is a description of how many solutions, otherwise there is a unique solution, the solution is each side row i-> column J traffic.

#include <stdio.h> #include <iostream> #include <map> #include <set> #include <stack># Include <vector> #include <math.h> #include <string.h> #include <queue> #include <string> #include <stdlib.h> #include <algorithm> #define LL long long#define _ll __int64#define eps 1e-12#define PI aco S ( -1.0) #define C 240#define S 20using namespace std;const int INF = 0x3f3f3f3f;const int MAXN = 810;const int MAXM = 16000 0+810;struct node{int u,v,w,next;} edge[maxm << 1];int cnt,head[maxn];int n,m,k,s,t;int nn[410],mm[410];int maxf    Low;int vis[maxn];int dis[maxn];void init () {cnt = 0; memset (head,-1,sizeof (Head));}    void Add (int u, int v, int f) {edge[cnt] = (struct node) {U,v,f,head[u]};    Head[u] = cnt++;    EDGE[CNT] = (struct node) {v,u,0,head[v]}; HEAD[V] = cnt++;}    BOOL BFs () {queue<int>que;    while (!que.empty ()) Que.pop ();    memset (dis,-1,sizeof (dis));    Dis[s] = 0;    Que.push (s);   while (!que.empty ()) {int u = que.front ();        Que.pop ();            for (int i = head[u]; i =-1; i = edge[i].next) {int v = EDGE[I].V;                if (dis[v] = =-1 && edge[i].w) {dis[v] = dis[u]+1;            Que.push (v);    }}} if (dis[t] = = 1) return false; return true;}    int dfs (int u, int delta) {if (U = = T | | delta = = 0) return delta;    int DD;    int ret = 0; for (int i = head[u]; I! =-1 && delta; i = edge[i].next) {if (dis[edge[i].v] = = dis[u]+1 && (dd            = DFS (Edge[i].v,min (DELTA,EDGE[I].W)))) {EDGE[I].W-= DD;            EDGE[I^1].W + = DD;            Delta-= DD;            RET + = DD;        if (delta = = 0) return ret; }}dis[u] = -1;return ret;}    int dinic () {int ret = 0;    while (BFS ()) {ret + = DFS (s,inf); } return ret;} int dfs_1 (int u,int fa) {for (int i=head[u]; i!=-1; i=edge[i].next) {if (i== (FA^1)) continue;            if (EDGE[I].W) {if (VIS[EDGE[I].V]) return 1;            Vis[edge[i].v]=1;            if (Dfs_1 (edge[i].v,i)) return 1;        vis[edge[i].v]=0; }} return 0;} void Putmat () {int f[410][410];p rintf ("unique\n"), for (int u = 1, u <= n; u++) {for (int i = head[u]; I! =-1; i = Edge[i]. Next) {int v = edge[i].v;if (V > N && v <= n+m) f[u][v-n] = K-EDGE[I].W;}} for (int i = 1; I <= n; i++) {for (int j = 1; j < M; j + +) printf ("%d", F[i][j]);p rintf ("%d\n", F[i][m]);}}        int main () {while (~SCANF ("%d%d%d", &n,&m,&k)) {init ();        s = 0;        t = n+m+1;        int sum1 = 0;        int sum2 = 0;            for (int i = 1; I <= n; i++) {scanf ("%d", &nn[i]);            Add (S,i,nn[i]);        Sum1 + = nn[i];for (int j = 1; j <= M; j + +) Add (i,j+n,k);            } for (int i = 1; I <= m; i++) {scanf ("%d", &mm[i]);            Add (I+n,t,mm[i]); Sum2 + = Mm[i];        } if (sum1! = sum2) {printf ("impossible\n"); }else{maxflow = Dinic (); if (maxflow! = sum1) {printf ("impossible\n");} Else{int flag = 0;memset (vis,0,sizeof (VIS)), for (int i = 1; I <= n; i++) {if (Dfs_1 (i,-1)) {flag = 1;break;}}    if (flag = = 1) printf ("Not unique\n"); Elseputmat ();}} } return 0;}

HDU 4888 Redraw Beautiful drawings (maximum flow, sentence ring)