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#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
const int INF = 1e9;
const int N = 205;
ifstream fin("cc.in");
ofstream fout("cc.out");
int n, maxFlow, minCost;
int cap[N][N], flow[N][N];
vector<pair<int, int>> g[N];
vector<int> t, dist;
void BellmanFordCoada(int s)
{
dist.assign(n * 2 + 5, INF);
vector<bool> inCoada(n * 2 + 5);
t.assign(n * 2 + 5, 0);
dist[s] = 0;
queue<int> q;
q.push(s);
inCoada[s] = true;
while(!q.empty())
{
int x = q.front();
q.pop();
inCoada[x] = false;
for(auto neigh : g[x])
{
int y = neigh.first;
int cost = neigh.second;
if(flow[x][y] != cap[x][y] && dist[x] + cost < dist[y])
{
dist[y] = dist[x] + cost;
t[y] = x;
if(!inCoada[y])
{
q.push(y);
inCoada[y] = true;
}
}
}
}
}
int maxFlowMinCost(int source, int sink)
{
maxFlow = 0;
minCost = 0;
do
{
BellmanFordCoada(source);
if(dist[sink] == INF)
break;
int fmin = 1 << 30;
for(int node = sink; node != source; node = t[node])
fmin = min(fmin, cap[t[node]][node] - flow[t[node]][node]);
if(fmin == 0)
continue;
maxFlow += fmin;
minCost += dist[sink] * fmin;
for(int node = sink; node != source; node = t[node])
{
flow[t[node]][node] += fmin;
flow[node][t[node]] -= fmin;
}
} while(dist[sink] != INF);
return minCost;
}
int main()
{
fin >> n;
for(int concurent = 1; concurent <= n; concurent++)
{
for(int calculator = 1; calculator <= n; calculator++)
{
int cost;
fin >> cost;
g[concurent].push_back({calculator + n, cost});
g[calculator + n].push_back({concurent, -cost});
cap[concurent][calculator + n] = 1;
}
}
// connect source with left and sink with right
for(int i = 1; i <= n; i++)
{
g[0].push_back({i, 0});
cap[0][i] = 1;
}
for(int i = n + 1; i <= n * 2; i++)
{
g[i].push_back({n * 2 + 1, 0});
cap[i][n * 2 + 1] = 1;
}
maxFlowMinCost(0, n * 2 + 1);
fout << minCost << '\n';
return 0;
}