/*
最小生成树
Prim算法（邻接矩阵）
*/
1 #include <iostream>
2 #include <cstdlib>
3 #include <cstdio>
4 #include <cstddef>
5 #include <iterator>
6 #include <algorithm>
7 #include <string>
8 #include <locale>
9 #include <cmath>
10 #include <vector>
11 #include <cstring>
12 #include <map>
13 #include <utility>
14 #include <queue>
15 #include <stack>
16 #include <set>
17 #include <functional>
18 using namespace std;
19 typedef pair<int, int> PII;
20 const int INF = 0x3f3f3f3f;
21 const int modPrime = 3046721;
22 const double eps = 1e-9;
23 const int MaxN = 110;
24 const int MaxM = 110;
25
26 int N;
27 int cost[MaxN][MaxN];
28 int minCost[MaxN];
29 bool used[MaxN];
30
31
32 void Solve()
33 {
34 fill(minCost, minCost + N, INF);
35 fill(used, used + N, false);
36 minCost[0] = 0;
37 int ans = 0;
38
39 while (true)
40 {
41 int v = -1;
42 for (int i = 0; i < N; ++i)
43 {
44 if (!used[i] && (-1 == v || minCost[i] < minCost[v]))
45 {
46 v = i;
47 }
48 }
49 if (v == -1)
50 {
51 break;
52 }
53 used[v] = true;
54 ans += minCost[v];
55 for (int i = 0; i < N; ++i)
56 {
57 minCost[i] = min(minCost[i], cost[v][i]);
58 }
59 }
60
61 printf("%d\n", ans);
62 }
63
64 int main()
65 {
66 #ifdef HOME
67 freopen("in", "r", stdin);
68 //freopen("out", "w", stdout);
69 #endif
70
71 scanf("%d", &N);
72 for (int i = 0; i < N; ++i)
73 {
74 for (int j = 0; j < N; ++j)
75 {
76 scanf("%d", &cost[i][j]);
77 }
78 }
79 Solve();
80
81 #ifdef HOME
82 cerr << "Time elapsed: " << clock() / CLOCKS_PER_SEC << " ms" << endl;
83 _CrtDumpMemoryLeaks();
84 #endif
85 return 0;
86 }
