poj 3308 Paratroopers 最小割—最大流

和方格取数类似的建图，基本上读完题就能看出来了，简单的最小割，至于取对数是常用方法，没什么好说的

网络流一般都是int的，double只要加一个eps精度判定就可以了~~

一次性编译 + 一次性ac~~看来我变强了。。。︿(￣︶￣)︽(￣︶￣)︿飞.飞.飞.

#include<iostream>#include<vector>#include<algorithm>#include<cstdio>#include<queue>#include<stack>#include<string>#include<map>#include<set>#include<cmath>#include<cassert>#include<cstring>#include<iomanip>using namespace std;#ifdef _WIN32#define i64 __int64#define format "%I64d\n"#else#define i64 long long#define format "%lld\n"#endif#define CC(m,what)memset(m,what,sizeof(m))#define FOR(i,a,b)for( int i = (a) ; i <= (b) ; i ++)#define FF(i,a)for( int i = 0 ; i < (a) ; i ++)#define FFD(i,a)for( int i = (a)-1 ; i >= 0 ; i --)#define SS(a)scanf("%d",&a)#define LL(a)((a)<<1)#define RR(a)(((a)<<1)+1)#define PP(n,m,a)puts("---");FF(i,n){FF(j,m)cout << a[i][j] << ' ';puts("");}#define pb              push_back#define CL(Q)           while(!Q.empty())Q.pop()#define MM(name,what)   memset(name,what,sizeof(name))#define readfreopen("in.txt","r",stdin)#define writefreopen("out.txt","w",stdout)const int inf = 0x3f3f3f3f;const double oo = 10e9;const double eps = 1e-10;const double PI = acos(-1.0);const int maxn=111;const int end=110;struct zz{    int from;    int to;    int id;    double c;}zx,tz;int T,m,n,l,tx,ty;double td;double sx[maxn];double sy[maxn];vector<zz>g[maxn];queue<int>q;int cen[maxn];inline void init(){       FF(i,maxn) g[i].clear();    return ;}bool bfs(){       CL(q);    MM(cen,-1);    cen[0] = 0;    q.push(0);    int now,to;    while(!q.empty())    {        now = q.front();        q.pop();        FF(i,g[now].size())        {            to = g[now][i].to;            if( g[now][i].c > eps && cen[to] == -1)            {                cen[to] = cen[now] + 1;                q.push(to);            }        }                   }    return cen[end] != -1; }double dfs(double flow = oo , int now = 0 ){    if(now == end)    {        return flow;    }    double temp,sum=0.0;    int to;    FF(i,g[now].size())    {        to = g[now][i].to;        if( cen[to] == cen[now] + 1  && flow - sum > eps && g[now][i].c > eps )        {            temp = dfs ( min ( flow - sum , g[now][i].c ) , to );            sum += temp;            g[now][i].c -= temp;            g[to][g[now][i].id].c += temp;        }    }              if(sum < eps) cen[now] = -1;                            return sum;}double dinic(){    double ans=0.0;    while( bfs() )    {        ans += dfs();    }        ans = exp (ans);        return ans;}int main(){    cin>>T;    while(T--)    {        cin>>m>>n>>l;           init();        for(int i=1;i<=m;i++)        {            cin>>td;            td = log(td);            sx[i] = td;        }        for(int i=1;i<=n;i++)        {               cin>>td;            td = log(td);            sy[i] = td;        }        FOR(i,1,m)         {            zx.from = 0;            zx.to = i;            zx.c = sx[i];            zx.id = g[i].size();            g[0].pb(zx);            swap (zx.from , zx.to);            zx.c = 0;            zx.id = g[0].size() - 1;            g[i].pb(zx);        }        FOR(i,1,n)        {            zx.from = 50 + i;            zx.to = end;            zx.c = sy[i];            zx.id = g[end].size();            g[50+i].pb(zx);            swap (zx.from , zx.to);            zx.c = 0;            zx.id = g[50+i].size() - 1;            g[end].pb(zx);        }        FOR(i,1,l)        {            cin>>tx>>ty;               zx.from = tx;            zx.to = ty + 50;            zx.c = oo;            zx.id = g[zx.to].size();            g[tx].pb(zx);            swap (zx.from , zx.to);            zx.c=0;            zx.id = g[tx].size() - 1;            g[zx.from].pb(zx);        }        cout.setf(ios::fixed);        cout<< setprecision(4) << dinic() <<endl;            }    return 0;   }