#include
#include
#include
#include
using namespace std;
const int maxn = 550;
const int INF = 0x3f3f3f3f;
int nx, ny, lx[maxn], ly[maxn];
bool visx[maxn], visy[maxn];
int linker[maxn], slack[maxn];
int G[maxn][maxn];
bool dfs(int x){
visx[x] = 1; //标记X的匈牙利树节点
for(int y = 1; y <= ny; y++){
if(visy[y]) continue;
int tmp = lx[x] + ly[y] - G[x][y];
if(tmp == 0){ //找到了一条可以加入相等子图的新边
visy[y] = 1; //标记Y的匈牙利树节点
if(linker[y] == -1 || dfs(linker[y])){ //找到了增广路
linker[y] = x;
return true;
}
}else if(slack[y] > tmp){ //更新松弛量
slack[y] = tmp;
}
}
return false;
}
int KM(){
memset(linker,-1,sizeof(linker)); //匹配数组
memset(ly,0,sizeof(ly)); //初始化Y节点顶标
for(int i = 1; i <= nx; i++){
lx[i] = -INF;
for(int j = 1; j <= ny; j++){
if(lx[i] slack[i]){ //Yi不在匈牙利树(交错树)中
d = slack[i];
}
}
for(int i = 1; i <= nx; i++){ //Xi在匈牙利树中,更新顶标
if(visx[i]){
lx[i] -= d;
}
}
for(int i = 1; i <= ny; i++){
if(visy[i]){ //Yi在匈牙利树中,更新顶标
ly[i] += d;
}else{ //更新松弛量
slack[i] -= d;
}
}
}
}
int ret = 0;
for(int i = 1; i <= ny; i++){ //求和
if(linker[i] != -1){
ret += G[linker[i]][i];
}
}
return ret;
}
int main(){
int n;
while(scanf("%d",&n)!=EOF){
memset(G,0,sizeof(G));
int c;
for(int i = 1; i <= n; i++){
for(int j = 1; j <= n; j++){
scanf("%d",&c);
G[i][j] = c;
}
}
nx = ny = n;
int res = KM();
printf("%d\n",res);
}
return 0;
}