HDOJ-1233 还是畅通工程(最小生成树)

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <vector>
#include <climits>
#include <set>

using namespace std;
#define maxn 105
int Graph[maxn][maxn];
int dis[maxn], num[maxn];
int main()
{
//    freopen("in.txt", "r", stdin);
int n;

while(scanf("%d", &n) == 1 && n)
{
for(int i = 1; i <= n*(n-1)/2; i++)
{
int a, b, c;

scanf("%d%d%d", &a, &b, &c);
Graph[a][b] = Graph[b][a] = c;
}
memset(num, 0, sizeof(num));
for(int i = 2; i <= n; i++)
dis[i] = Graph[1][i];
num[1] = 1;
int k = 1, sum = 0;;
for(int i = 2; i <= n; i++)
{
int mins = INT_MAX, p;
for(int j = 2; j <= n; j++)
{
if(!num[j] && mins > dis[j])
{
p = j;
mins = dis[j];
}
}
k = p;
sum += mins;
num[k] = 1;
for(int j = 2; j <= n; j++)
{
if(!num[j] && Graph[k][j] < dis[j])
{
dis[j] = Graph[k][j];
}
}
}
cout << sum << endl;
}

return 0;
}

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <cmath>

using namespace std;
#define maxn 105

struct Edge{
friend bool operator < (const Edge &a, const Edge &b)
{
return a.d < b.d;
}
int x, y, d;
}edge[5005];
int p[maxn];

int found(int k)
{
int s = k;
while(s != p[s])
s = p[s];

int j;
while(k != p[k])
{
j = p[k];
p[k] = s;
k = j;
}

return s;
}
int main()
{
//freopen("in.txt", "r", stdin);
int n;

while(scanf("%d", &n) == 1 && n)
{
for(int i = 1; i <= n*(n-1)/2; i++)
{
int a, b, c;

scanf("%d%d%d", &a, &b, &c);
edge[i].x = a;
edge[i].y = b;
edge[i].d = c;
}
for(int i = 1; i <= n; i++)
p[i] = i;
sort(edge+1, edge+n*(n-1)/2+1);
int cnt = 0, sum = 0;
for(int i = 1; i <= n*(n-1)/2 && cnt != n-1; i++)
{
int k1 = found(edge[i].x), k2 = found(edge[i].y);
if(k1 != k2)
{
cnt++;
sum += edge[i].d;
p[k1] = k2;
}
}
cout << sum << endl;
}

return 0;
}