hdu-携程复赛-最短路径的代价-抠图+最小割

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被数据范围坑死了。。。
说好的m<=10000,改成了m<=11000....
把所有最短路涉及到的边抠出来。
然后建图，边的权值为边的c。
然后对图求一个最小割。
最小割割掉的所有的边即为要选调的边。
#include <stdio.h>#include <iostream>#include <algorithm>#include <string.h>#include<queue>using namespace std;#define INF 99999999const int maxn =1110;const int maxm =25000;const int oo = 1<<29;struct Arclist{    int cnt, head[maxn], dis[maxn];    int cur[maxn], pre[maxn], gap[maxn], aug[maxn];    struct node    {        int u, v, w, next;    } edge[maxm];    void init(int n)    {        cnt = 0;        std::fill_n(head, n+1, -1);    }    void add(int u, int v, int w)    {        edge[cnt].u = u;        edge[cnt].v = v;        edge[cnt].w = w;        edge[cnt].next = head[u];        head[u] = cnt++;        edge[cnt].u = v;        edge[cnt].v = u;        edge[cnt].w = 0;        edge[cnt].next = head[v];        head[v] = cnt++;    }    int sap(int s, int e, int n)    {        int max_flow = 0, u = s;        int mindis;        for(int i = 0; i <= n; i++)        {            cur[i] = head[i];            dis[i] = 0;            gap[i] = 0;        }        aug[s] = oo;        pre[s] = -1;        gap[0] = n;        while(dis[s]<n)        {            bool flag = false;            if(u==e)            {                max_flow += aug[e];                for(int v = pre[e]; v != -1; v = pre[v])                {                    int id = cur[v];                    edge[id].w -= aug[e];                    edge[id^1].w += aug[e];                    aug[v] -= aug[e];                    if(edge[id].w==0) u = v;                }            }            for(int id = cur[u]; id != -1; id = edge[id].next)            {                int v = edge[id].v;                if(edge[id].w>0 && dis[u]==dis[v]+1)                {                    flag = true;                    pre[v] = u;                    cur[u] = id;                    aug[v] = std::min(aug[u], edge[id].w);                    u = v;                    break;                }            }            if(flag==false)            {                if(--gap[dis[u]]==0) break;                mindis = n;                cur[u] = head[u];                for(int id = head[u]; id != -1; id = edge[id].next)                {                    int v = edge[id].v;                    if(edge[id].w>0 && dis[v]<mindis)                    {                        mindis = dis[v];                        cur[u] = id;                    }                }                dis[u] = mindis+1;                ++gap[dis[u]];                if(u!=s) u = pre[u];            }        }        return max_flow;    }} G;struct gra{    struct list    {        int u,v,w,c,next;    } edge[maxm];    int head[maxn];    int nums;    void init()    {        nums=0;        memset(head,-1,sizeof(head));    }    void add(int u,int v,int w,int c)    {        edge[nums].u=u;edge[nums].v=v;        edge[nums].c=c;edge[nums].w=w;        edge[nums].next=head[u];head[u]=nums++;    }}gs;int dij(int st,int ed,int n){    int i;    int dis[maxn];    int vis[maxn];    for(i=1;i<=n;i++)    {        dis[i]=INF;        vis[i]=0;    }    dis[st]=0;    while(1)    {        int minn=INF;        int x;        for(i=1;i<=n;i++)        {            if(vis[i])continue;            if(minn>dis[i])            {                minn=dis[i];                x=i;            }        }        if(minn==INF)break;        vis[x]=1;        for(i=gs.head[x];i!=-1;i=gs.edge[i].next)        {            int v=gs.edge[i].v;            int w=gs.edge[i].w;            if(vis[v])continue;            if(dis[v]>dis[x]+w)dis[v]=dis[x]+w;        }    }    //for(i=1;i<=n;i++)cout<<dis[i]<<" ";   // cout<<endl;    queue<int>que;    while(!que.empty())que.pop();    que.push(ed);    memset(vis,0,sizeof(vis));    vis[ed]=1;    while(!que.empty())    {        int x=que.front();        que.pop();        if(x==st)continue;        for(i=gs.head[x];i!=-1;i=gs.edge[i].next)        {            int u=gs.edge[i].v;            int w=gs.edge[i].w;            int c=gs.edge[i].c;            if(dis[u]+w==dis[x])            {              //  cout<<u<<"-"<<x<<":"<<c<<endl;                G.add(u,x,c);                if(!vis[u])que.push(u);                vis[u]=1;            }        }    }    return G.sap(st,ed,n);}int main(){    int n,m,st,ed,a,b,w,c;    while(~scanf("%d%d",&n,&m)&&(n||m))    {        gs.init();        scanf("%d%d",&st,&ed);        for(int i=1;i<=m;i++)        {            scanf("%d%d%d%d",&a,&b,&w,&c);            gs.add(a,b,w,c);            gs.add(b,a,w,c);        }        G.init(maxn-1);        cout<<dij(st,ed,n)<<endl;    }    return 0;}
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