bzoj1083: [SCOI2005]繁忙的都市 瓶颈生成树
https://www.lydsy.com/JudgeOnline/problem.php?id=1083
题意:给你一个图,求生成树最大边权最小值
就是求瓶颈生成树(生成树中最大边权最小),最小生成树一定是瓶颈生成树,但是瓶颈生成树不一定是最小生成树,最小瓶颈生成树一定是最小生成树
/************************************************************** Problem: 1083 User: walfy Language: C++ Result: Accepted Time:40 ms Memory:2420 kb ****************************************************************/ //#pragma comment(linker, "/stack:200000000") //#pragma GCC optimize("Ofast,no-stack-protector") //#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native") //#pragma GCC optimize("unroll-loops") #include<bits/stdc++.h> #define fi first #define se second #define mp make_pair #define pb push_back #define pi acos(-1.0) #define ll long long #define vi vector<int> #define mod 1000000007 #define C 0.5772156649 #define ls l,m,rt<<1 #define rs m+1,r,rt<<1|1 #define pil pair<int,ll> #define pli pair<ll,int> #define pii pair<int,int> #define cd complex<double> #define ull unsigned long long #define base 1000000000000000000 #define fio ios::sync_with_stdio(false);cin.tie(0) using namespace std; const double g=10.0,eps=1e-12; const int N=300+10,maxn=N*N+10,inf=0x3f3f3f3f,INF=0x3f3f3f3f3f3f3f3f; struct edge{ int u,v,c; bool operator <(const edge&rhs)const{ return c<rhs.c; } }e[maxn]; int fa[N]; int Find(int x) { return fa[x]==x?x:fa[x]=Find(fa[x]); } int main() { int n,m; scanf("%d%d",&n,&m); for(int i=1;i<=n;i++)fa[i]=i; for(int i=0;i<m;i++)scanf("%d%d%d",&e[i].u,&e[i].v,&e[i].c); sort(e,e+m); int ans=0; for(int i=0;i<m;i++) { int x=e[i].u,y=e[i].v; int fx=Find(x),fy=Find(y); if(fx!=fy) { fa[fx]=fy; ans=max(ans,e[i].c); } } printf("%d %d\n",n-1,ans); return 0; } /*********************** ***********************/