[日常摸鱼]bzoj1083[SCOI2005]繁忙的都市-最小生成树

Posted 2020-10-22 yoooshinow

我也不知道为什么我要来写这个…怕是写水题写上瘾了（bu

#include<cstdio>
#include<algorithm>
#define rep(i,n) for(register int i=1;i<=n;i++)
const int N=10005;
struct edge
{
    int u,v,c;
}e[N];
int n,m,mx,s[N],pre[N];
inline int find(int x){return pre[x]==x?x:find(pre[x]);}
inline int max(int a,int b){return a>b?a:b;} 
inline void unite(int x,int y)
{
    int t=s[x]+s[y];
    if(s[x]>s[y])pre[y]=x,s[x]=s[y]=t;
    else pre[x]=y,s[x]=s[y]=t;
}
inline bool cmp(const edge &x,const edge &y)
{
    return x.c<y.c;
}
int main()
{
    scanf("%d%d",&n,&m);
    rep(i,n)pre[i]=i,s[i]=1;
    rep(i,m)scanf("%d%d%d",&e[i].u,&e[i].v,&e[i].c);
    std::sort(e+1,e+m+1,cmp);
    rep(i,m)
    {
        int u,v,c;u=e[i].u;v=e[i].v;c=e[i].c;
        int fu=find(u),fv=find(v);
        if(fu==fv)continue;
        unite(fu,fv);mx=max(mx,c);
    }
    printf("%d %d",n-1,mx);
}