ural 1160

最小生成树  第一次敲 套用几个函数 其实挺容易的

#include <cstdio>
#include <cstring>
#include <vector>
#include <algorithm>
using namespace std;
struct node
{
    int u,v,w;
    void f(int a, int b, int c)
    {
        u = a;
        v = b;
        w = c;
    }
    bool operator < (const node & e) const
    {
        return w < e.w;
    }
};
vector<node>q,qq;
int p[2000],r[2000];

int findd(int x)
{
    return p[x] == x ? x : p[x] = findd(p[x]);
}
int main()
{
    int n,m;
    node cc;
    scanf("%d%d",&n,&m);
    for(int i = 0; i < m; i++)
    {
        int a,b,c;
        scanf("%d%d%d",&a,&b,&c);
        cc.f(a,b,c);
        q.push_back(cc);
    }
    sort(q.begin(), q.end());
    int ans = 0;
    for(int i = 0; i <= n; i++)
        p[i] = i;
    for(int i = 0; i < m; i++)
    {
        int x = findd(q[i].u), y = findd(q[i].v);
        if(x != y)
        {
            ans = q[i].w;
            qq.push_back(q[i]);
            p[x] = y;
        }
    }
    printf("%d\n",ans);
    int len = qq.size();
    printf("%d\n",len);
    for(int i = 0; i < len; i ++)
        printf("%d %d\n",qq[i].u,qq[i].v);
    return 0;
}