POJ 1459 Power Network, maximum flow, multi-source multi-sinks

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Multi-source multi-sink maximum flow, virtual One source point s ' and a meeting point T ', the original source point, the sink point to their edge.

#include <cstdiO> #include <cstring> #include <iostream> #include <algorithm> #include < Queue> #include <vector>using namespace Std;const int maxn = + 5;const int INF = 100000000;struct edge{int From, to, cap, flow;};    struct dinic{int n, m, S, t;    Vector<edge> edges;    Vector<int> G[MAXN];    BOOL VIS[MAXN];    int D[MAXN];    int CUR[MAXN];        void init (int n) {this->n = n;        for (int i=0; i<=n; ++i) g[i].clear ();    Edges.clear ();        } void Addedge (int from, int to, int caps) {Edges.push_back (Edge) {from, to, Cap, 0});        Edges.push_back (Edge) {To, from, 0, 0});        m = Edges.size ();        G[from].push_back (m-2);    G[to].push_back (m-1);        } bool BFS () {memset (Vis, 0, sizeof vis);        Queue<int> Q;        Q.push (s);        Vis[s] = 1;        D[s] = 0; while (! Q.empty ()) {int x = Q.front ();            Q.pop (); for (int i=0; i<g[x].sizE ();                ++i) {edge& e = edges[g[x][i]];                    if (!vis[e.to] && e.cap > E.flow) {vis[e.to] = 1;                    D[e.to] = d[x] + 1;                Q.push (e.to);    }}} return vis[t];        } int DFS (int x, int a) {if (x = = T | | a = = 0) return A;        int flow = 0, F;            for (int& i = cur[x]; i<g[x].size (); ++i) {edge& e = edges[g[x][i]];                if (d[x] + 1 = = D[e.to] && (F=dfs (e.to, Min (a,e.cap-e.flow))) >0) {e.flow + = f;                Edges[g[x][i]^1].flow-= f;                Flow + + F;                A-= f;            if (a==0) break;    }} return flow;        } int Maxflow (int s, int t) {this->s = s; this->t =t;        int flow = 0;            while (BFS ()) {memset (cur, 0, sizeof cur);     Flow + = DFS (s, INF);   } return flow;    }};D inic Solver;int main () {int n, NP, NC, M;    Char ch;    int x, y, Z;        while (~SCANF ("%d%d%d%d", &n, &AMP;NP, &AMP;NC, &m)) {int s = 0, t = n+1;        Solver.init (t+2);            for (int i=1; i<=m; ++i) {cin>>ch>>x>>ch>>y>>ch>>z;            if (x==y) continue; Solver.        Addedge (x+1, y+1, z);            } for (int i=1; i<=np; ++i) {cin>>ch>>x>>ch>>z; Solver.        Addedge (S, x+1, z);            } for (int i=1; i<=nc; ++i) {cin>>ch>>x>>ch>>z; Solver.        Addedge (x+1, T, z); } int ans = solver.        Maxflow (s,t);    printf ("%d\n", ans); } return 0;}