网络流+二分+枚举区间
#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
#include<queue>
using namespace std;
typedef long long ll;
const int N=1020+10;
const int M=5e4+10;
const int INF=0x7f7f7f7f;
struct Edge
{
int to,nxt,cap,flow;
}edge[M];
int tot,first[N];
void addedge(int u,int v,int w,int rw=0)
{
edge[tot].to=v;edge[tot].cap=w;edge[tot].flow=0;
edge[tot].nxt=first[u];first[u]=tot++;
edge[tot].to=u;edge[tot].cap=rw;edge[tot].flow=0;
edge[tot].nxt=first[v];first[v]=tot++;
}
void init()
{
tot=0;
memset(first,-1,sizeof(first));
}
int gap[N],dep[N],cur[N];
int Q[N],S[N];
void bfs(int s)
{
memset(gap,0,sizeof(gap));
memset(dep,-1,sizeof(dep));
int q0=0,q1=0;
Q[q1++]=s;
dep[s]=0;
gap[0]=1;
while(q0<q1)
{
int u=Q[q0++];
for(int i=first[u];i!=-1;i=edge[i].nxt)
{
int v=edge[i].to;
if(dep[v]!=-1) continue;
Q[q1++]=v;
dep[v]=dep[u]+1;
gap[dep[v]]++;
}
}
}
int sap(int s,int t,int n)
{
int ans=0;
bfs(t);
memcpy(cur,first,sizeof(first));
int top=0;
int u=s;
while(dep[s]<n)
{
if(u==t)
{
int Min=INF;
int inser;
for(int i=0;i<top;i++)
if(Min>edge[S[i]].cap-edge[S[i]].flow)
{
Min=edge[S[i]].cap-edge[S[i]].flow;
inser=i;
}
for(int i=0;i<top;i++)
{
edge[S[i]].flow+=Min;
edge[S[i]^1].flow-=Min;
}
ans+=Min;
top=inser;
u=edge[S[top]^1].to;
}
bool flag=false;
int v;
for(int i=cur[u];i!=-1;i=edge[i].nxt)
{
v=edge[i].to;
if(edge[i].cap-edge[i].flow&&dep[v]+1==dep[u])
{
flag=true;
cur[u]=S[top++]=i;
break;
}
}
if(flag)
{
u=v;
continue;
}
gap[dep[u]]--;
if(!gap[dep[u]]) return ans;
int Min=n;
for(int i=first[u];i!=-1;i=edge[i].nxt)
if(edge[i].cap-edge[i].flow&&Min>dep[edge[i].to])
{
Min=dep[edge[i].to];
cur[u]=i;
}
dep[u]=Min+1;
gap[dep[u]]++;
if(u!=s) u=edge[S[--top]^1].to;
}
return ans;
}
int g[N][N];
int num[N];
int main()
{
int n,m,a;
while(~scanf("%d%d",&n,&m))
{
int s=n+m,t=s+1;
for(int i=0;i<n;i++)
for(int j=0;j<m;j++)
{
scanf("%d",&a);
g[i][a+n-1]=j+1;
}
for(int i=n;i<s;i++)
scanf("%d",&num[i]);
int ans=m,l=1,r=m;
while(l<=r)
{
int mid=(l+r)>>1;
bool flag=false;
for(int k=1;k+mid-1<=m;k++)
{
init();
for(int i=0;i<n;i++)
addedge(s,i,1);
for(int i=n;i<s;i++)
addedge(i,t,num[i]);
for(int i=0;i<n;i++)
for(int j=n;j<s;j++)
if(g[i][j]>=k&&g[i][j]<=k+mid-1)
addedge(i,j,1);
int num=sap(s,t,t+1);
if(num==n)
{
flag=true;
break;
}
}
if(!flag)
{
l=mid+1;
}
else
{
ans=mid;
r=mid-1;
}
}
printf("%d\n",ans);
}
return 0;
}