1 #include<bits/stdc++.h>
2 using namespace std;
3 const int maxn=5005;
4 const int INF=0x3f3f3f3f;
5 inline void read(int &tmp)
6 {
7 int x=1;char c=getchar();
8 for(tmp=0;!isdigit(c);c=getchar()) if(c=='-') x=-1;
9 for(;isdigit(c);tmp=tmp*10+c-48,c=getchar());
10 tmp*=x;
11 }
12 int n,sum,tot,m,mp[maxn][maxn],w[maxn];
13 typedef pair<int,int> P;
14 priority_queue< P,vector<P>,greater<P> >q;
15 bool v[maxn];
16 void Prim()
17 {
18 memset(w,0x3f,sizeof(w));
19 w[1]=0;q.push(make_pair(0,1));
20 while(!q.empty())
21 {
22 int Top=q.top().second;q.pop();
23 if(v[Top]) continue;
24 v[Top]=1;sum+=w[Top];++tot;
25 for(int i=1;i<=n;i++)
26 if(mp[Top][i]<w[i]&&mp[Top][i]>0&&v[i]==false) {w[i]=mp[Top][i];q.push(make_pair(w[i],i));}
27 }
28 }
29 int main()
30 {
31 read(n);
32 for(int i=1;i<=n;i++)
33 for(int j=1;j<=n;j++)
34 {read(mp[i][j]);if(i==j) mp[i][j]=INF;}
35 Prim();
36 printf("%d",sum);
37 return 0;
38 }
