【模板】最小生成树Kruskal

洛谷3366

 #include<cstdio>
 #include<algorithm>
 using namespace std;
 const int maxn=,maxm=;
 int n,m,fa[maxn],tot=,ans=;
 struct edge{int x,y,dis;}a[maxm];
 void read(int &k){
     k=; int f=; char c=getchar();
     while (c<''||c>'')c=='-'&&(f=-),c=getchar();
     while (''<=c&&c<='')k=k*+c-'',c=getchar();
     k*=f;
 }
 bool cmp(edge a,edge b){return a.dis<b.dis;}
 int find(int x){return fa[x]==x?x:fa[x]=find(fa[x]);}
 int main(){
     read(n); read(m);
     for (int i=;i<=n;i++) fa[i]=i;
     for (int i=;i<=m;i++) read(a[i].x),read(a[i].y),read(a[i].dis);
     sort(a+,a+m+,cmp);
     for (int i=,x,y;i<=m;i++){
         if (find(x=a[i].x)!=find(y=a[i].y)) fa[find(x)]=find(y),ans+=a[i].dis,tot++;
         if (tot==n-) break;
     }
     if (tot==n-) printf("%d",ans); else printf("orz");
 }