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#include<fstream>
#include<algorithm>
#include<vector>
#include<queue>
#define INF 2000000000
using namespace std;
ifstream f("cc.in");
ofstream g("cc.out");
struct nod
{
int x,poz;
};
vector<nod>a[205];
nod tata[205];
int n,s,d,flux,sol,r[20402],z[20402],dist[205],dist2[205],realdist[205];
bool inq[205];
queue<int>q;
struct elem
{
int x,dist;
inline bool operator < (const elem &a) const
{
return dist>a.dist;
}
};
priority_queue<elem>pq;
inline bool dijkstra()
{
int i,l,Z;
elem p;
for(i=1;i<=n;i++)
dist[i]=INF,tata[i]={0,0};
pq.push({s,0});
dist[s]=0;
dist2[s]=0;
while(!pq.empty())
{
p=pq.top();
pq.pop();
if(p.dist==dist[p.x])
{
l=a[p.x].size();
for(i=0;i<l;i++)
{
Z=realdist[p.x]-realdist[a[p.x][i].x]+z[a[p.x][i].poz];
if(r[a[p.x][i].poz]>0&&dist[a[p.x][i].x]>dist[p.x]+Z)
{
dist[a[p.x][i].x]=dist[p.x]+Z;
dist2[a[p.x][i].x]=dist2[p.x]+z[a[p.x][i].poz];
tata[a[p.x][i].x].x=p.x;
tata[a[p.x][i].x].poz=a[p.x][i].poz;
pq.push({a[p.x][i].x,dist[a[p.x][i].x]});
}
}
}
}
for(i=1;i<=n;i++)
realdist[i]=dist2[i];
return dist[d]!=INF;
}
inline void bellman_ford()
{
int i,l,p;
for(i=1;i<=n;i++)
realdist[i]=INF;
realdist[s]=0;
q.push(s);
inq[s]=1;
while(!q.empty())
{
p=q.front();
q.pop();
inq[p]=0;
l=a[p].size();
for(i=0;i<l;i++)
if(r[a[p][i].poz]>0&&realdist[a[p][i].x]>realdist[p]+z[a[p][i].poz])
{
realdist[a[p][i].x]=realdist[p]+z[a[p][i].poz];
if(inq[a[p][i].x]==0)
{
q.push(a[p][i].x);
inq[a[p][i].x]=1;
}
}
}
}
inline void fmcm()
{
int i,flow,cost;
bellman_ford();
while(dijkstra()!=0)
{
flow=INF;
for(i=d;i!=s;i=tata[i].x)
{
flow=min(flow,r[tata[i].poz]);
if(flow==0)
break;
}
if(flow!=0&&flow!=INF)
{
cost=0;
for(i=d;i!=s;i=tata[i].x)
{
r[tata[i].poz]-=flow;
r[tata[i].poz^1]+=flow;
cost+=z[tata[i].poz];
}
flux+=flow;
sol+=flow*cost;
}
}
}
int main()
{
int i,x,k=0,j;
f>>n;
s=2*n+1;
d=2*n+2;
for(i=1;i<=n;i++)
for(j=1;j<=n;j++)
{
f>>x;
r[k]=1;
z[k]=x;
a[i].push_back({j+n,k});
k++;
r[k]=0;
z[k]=-x;
a[j+n].push_back({i,k});
k++;
}
for(i=1;i<=n;i++)
{
r[k]=1;
z[k]=0;
a[s].push_back({i,k});
k++;
r[k]=0;
z[k]=0;
a[i].push_back({s,k});
k++;
r[k]=1;
z[k]=0;
a[i+n].push_back({d,k});
k++;
r[k]=0;
z[k]=0;
a[d].push_back({i+n,k});
k++;
}
n=n*2+2;
fmcm();
g<<sol;
return 0;
}