ZOJ 3229 Shoot the Bullet [上下界最大流]

ZOJ 3229 Shoot the Bullet

题意：此生无悔入东方

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上下界最大流

spj挂掉了我也不知道对不对，把代码放这里吧以后正常了可能会评测一下

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
typedef long long ll;
const int N=2005, M=4e5+5, INF=1e9;
inline ll read(){
    char c=getchar();ll x=0,f=1;
    while(c<'0'||c>'9'){if(c=='-')f=-1;c=getchar();}
    while(c>='0'&&c<='9'){x=x*10+c-'0';c=getchar();}
    return x*f;
}

int n, m, extra[N], s, t, tot, c, b, x, l, r;
int a[370][1005];
struct edge{int v, c, f, ne, lower;}e[M];
int cnt=1, h[N];
inline int ins(int u, int v, int c, int b=0) { //printf("ins %d %d  %d  %d\n",u,v,c,b);
	e[++cnt]=(edge){v, c, 0, h[u], b}; h[u]=cnt;
	e[++cnt]=(edge){u, 0, 0, h[v], b}; h[v]=cnt;
	return cnt-1;
}
int q[N], head, tail, vis[N], d[N], cur[N];
bool bfs(int s, int t) {
	memset(vis, 0, sizeof(vis));
	head=tail=1;
	q[tail++]=s; d[s]=0; vis[s]=1;
	while(head!=tail) {
		int u=q[head++];
		for(int i=h[u];i;i=e[i].ne)
			if(!vis[e[i].v] && e[i].c>e[i].f) {
				vis[e[i].v]=1; d[e[i].v]=d[u]+1;
				q[tail++]=e[i].v;
				if(e[i].v == t) return true;
			}
	}
	return false;
}
int dfs(int u, int a, int t) {
	if(u==t || a==0) return a;
	int flow=0, f;
	for(int &i=cur[u];i;i=e[i].ne)
		if(d[e[i].v]==d[u]+1 && (f=dfs(e[i].v, min(a, e[i].c-e[i].f), t))>0) {
			flow+=f;
			e[i].f+=f;
			e[i^1].f-=f;
			a-=f;
			if(a==0) break;
		}
	if(a) d[u]=-1;
	return flow;
}
int dinic(int s, int t) {
	int flow=0;
	while(bfs(s, t)) {
		for(int i=0; i<=tot; i++) cur[i]=h[i];
		flow+=dfs(s, INF, t);
	}
	return flow;
}

int main() {
	freopen("in","r",stdin);
	while(scanf("%d%d",&n,&m)!=EOF) {
		s=0; t=n+m+1;
		cnt=1; memset(h,0,sizeof(h)); memset(extra, 0, sizeof(extra));
		for(int i=1; i<=m; i++) b=read(), ins(n+i, t, INF, b), extra[n+i]-=b, extra[t]+=b;
		for(int i=1; i<=n; i++) {
			a[i][0]=read();
			c=read(); ins(s, i, c, 0);
			for(int j=1; j<=a[i][0]; j++)
				x=read()+1, l=read(), r=read(), a[i][j]=ins(i, n+x, r-l, l), extra[i]-=l, extra[n+x]+=l;
		}

		int ss=n+m+2, tt=n+m+3, sum=0;
		tot=n+m+3;
		for(int i=s; i<=t; i++) {
			if(extra[i] > 0) ins(ss, i, extra[i]), sum+=extra[i];
			if(extra[i] < 0) ins(i, tt, -extra[i]);
		}
		ins(t, s, INF);
		int flow=dinic(ss, tt); //printf("sum %d %d\n",sum,flow); 

		if(flow != sum) puts("-1");
		else {
			printf("look %d\n",e[cnt-1].f);
			//e[cnt-1]=e[cnt]=edge();
			e[cnt].f=0;
			printf("%d\n", dinic(s, t));
			for(int i=1; i<=n; i++)
				for(int j=1; j<=a[i][0]; j++) x=a[i][j], printf("%d\n", e[x].f + e[x].lower);
		}
		puts("");
	}
	return 0;
}