所以您是不知道如何找死循环然后让万能的谷民帮您找么?
by MatrixCascade @ 2021-01-25 08:01:40
@[MatrixCascade](/user/154101) ~~差不多吧,只是我不知道建图哪里错了~~
by 听取MLE声一片 @ 2021-01-25 08:09:38
万能的谷民啊,我看什么都是网络流怎么办啊(滑稽
by 听取MLE声一片 @ 2021-01-25 08:11:13
@[听取MLE声一片](/user/253738) ~~那就用网络流做呗,说不定能比暴力多过几个点呢~~
by Alan_Zhao @ 2021-01-25 08:20:05
@[Alan_Zhao](/user/225625) 大草
by 听取MLE声一片 @ 2021-01-25 08:24:15
@[听取MLE声一片](/user/253738) 你建图没挂 应该是 EK 挂了
by Spasmodic @ 2021-01-25 08:31:39
@[听取MLE声一片](/user/253738) ~~dinic 不香吗,为啥要用 EK~~
by Alan_Zhao @ 2021-01-25 08:36:17
@[Alan_Zhao](/user/225625) ~~还没来得及改~~
by 听取MLE声一片 @ 2021-01-25 08:39:35
虽然我知道你早已 A 了此题, 但我还是要来帮以前的你 debug, 以此来练习我 de 的能力
文中有两处错误,
1. SPFA时的 `d` 数组初始化没完全.
2. 第二次 EK 前 `cost` 没有初始化
```cpp
#include<iostream>
#include<cstdio>
#include<cmath>
#include<string>
#include<cstring>
#include<algorithm>
#include<queue>
#include<stack>
#include<vector>
#include<map>
#include<complex>
using namespace std;
#define QAQ(x) cout<<x<<endl, exit(0);
inline int read(){
int x=0,f=1;char ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
return x*f;
}
const int inf=2147483647;
int maxn,cost;
int top=1,head[5001];
int dis[5001];
int n,m,s,t,book[5001],c[5001][5001],d[5001],e[5001];
struct point{
int v,w,val,next;
}a[100001];
struct B{
int fa;
int v;
}b[5001];
inline void add(int u,int v,int val,int w){
a[++top].v=v;
a[top].val=val;
a[top].w=w;
a[top].next=head[u];
head[u]=top;
}
bool spfa(){
queue<int> q;
memset(b,0,sizeof(b));
memset(book,0,sizeof(book));
for(int i=0;i<=n+m+1;i++) // 注意结点数量
dis[i]=inf;
dis[s]=0;
q.push(s);
book[s]=1;
while(!q.empty()){
int u=q.front();
book[u]=0;
q.pop();
for(int i=head[u];i;i=a[i].next){
int v=a[i].v,w=a[i].w;
if(a[i].val>0&&dis[v]>dis[u]+w){
dis[v]=dis[u]+w;
b[v].fa=u,b[v].v=i;
if(book[v]==0){
q.push(v);
book[v]=1;
}
}
}
}
return dis[t]!=inf;
}
void EK(){
while(spfa()){
int minn=inf;
for(int i=t;i!=s;i=b[i].fa)
minn=min(minn,a[b[i].v].val);
for(int i=t;i!=s;i=b[i].fa){
a[b[i].v].val-=minn;
a[b[i].v^1].val+=minn;
}
maxn+=minn;
cost+=minn*dis[t];
}
return;
}
int main()
{
m=read(),n=read();
s=0;
t=m+n+1;
for(int i=1;i<=m;i++){
d[i]=read();
add(s,i,d[i],0);
add(i,s,0,0);
}
for(int i=1;i<=n;i++){
e[i]=read();
add(i+m,t,e[i],0);
add(t,i+m,0,0);
}
for(int i=1;i<=m;i++)
for(int j=1;j<=n;j++){
c[i][j]=read();
add(i,j+m,inf,c[i][j]);
add(j+m,i,0,-c[i][j]);
}
EK();
cout<<cost<<endl;
cost = 0; // 其他都初始化了, 就 cost 没清零...
top=1;
memset(head,0,sizeof(head));
for(int i=1;i<=m;i++){
add(s,i,d[i],0);
add(i,s,0,0);
}
for(int i=1;i<=n;i++){
add(i+m,t,e[i],0);
add(t,i+m,0,0);
}
for(int i=1;i<=m;i++)
for(int j=1;j<=n;j++){
add(i,j+m,inf,-c[i][j]);
add(j+m,i,0,c[i][j]);
}
EK();
cout<<-cost;
return 0;
}
```
by OldPan @ 2022-05-03 09:48:32
@[OldPan](/user/374291) 您的MD爆了...
by FateReset_ @ 2023-07-25 21:00:21