zoukankan      html  css  js  c++  java
  • poj 3107 树重心

    http://acm.hust.edu.cn/vjudge/problem/18069

    和poj 1655差不多:http://www.cnblogs.com/qlky/p/5780933.html

    区别就是要记录所有的重心

    #include <iostream>
    #include <string>
    #include <cstring>
    #include <cstdlib>
    #include <cstdio>
    #include <cmath>
    #include <algorithm>
    #include <stack>
    #include <queue>
    #include <cctype>
    #include <vector>
    #include <iterator>
    #include <set>
    #include <map>
    #include <sstream>
    using namespace std;
    
    #define mem(a,b) memset(a,b,sizeof(a))
    #define pf printf
    #define sf scanf
    #define spf sprintf
    #define pb push_back
    #define debug printf("!
    ")
    #define MAXN 50000+5
    #define MAX(a,b) a>b?a:b
    #define blank pf("
    ")
    #define LL long long
    #define ALL(x) x.begin(),x.end()
    #define INS(x) inserter(x,x.begin())
    #define pqueue priority_queue
    #define INF 0x3f3f3f3f
    
    #define ls (rt<<1)
    #define rs (rt<<1|1)
    
    int n,m;
    
    int ptr = 1,head[MAXN],vis[MAXN];
    
    int res,ans[MAXN],son[MAXN],num=0;
    
    struct node
    {
        int y,val,next;
    }tree[MAXN<<1];
    
    void add(int fa,int son)
    {
        tree[ptr].y = son;
        tree[ptr].next = head[fa];
        head[fa] = ptr++;
    }
    
    void dfs(int root)
    {
        vis[root] = 1;
        son[root] = 0;
        int tmp = 0;
        for(int i=head[root];i!=-1;i=tree[i].next)
        {
            int y = tree[i].y;
            if(vis[y]) continue;
            dfs(y);
            son[root] += son[y]+1;
            tmp = max(son[y]+1,tmp);
        }
        tmp = max(tmp,n-son[root]-1);
        if(tmp<res)
        {
            ans[0] = root;
            num = 1;
            res = tmp;
        }
        else if(tmp == res) ans[num++] = root;
    }
    
    
    int main()
    {
        int i,j,t,kase=1;
        while(~sf("%d",&n))
        {
            mem(tree,0);
            mem(head,-1);
            mem(vis,0);
            mem(ans,0);
            res=INF;
            ptr = 1;
            num = 0;
            int x,y;
            for(i=1;i<n;i++)
            {
                sf("%d%d",&x,&y);
                add(x,y);
                add(y,x);
            }
            dfs(1);
            sort(ans,ans+num);
            pf("%d",ans[0]);
            for(i=1;i<num;i++) pf(" %d",ans[i]);
            blank;
        }
        return 0;
    }
  • 相关阅读:
    蓝桥杯2016初赛
    蓝桥杯2016初赛
    蓝桥杯2016初赛
    蓝桥杯2015初赛
    关于VS本身遇到的一些相关问题
    VS的一些常用快捷键
    蓝桥杯2015初赛
    Luogu P1704 寻找最优美做题曲线
    POI2009 LYZ-Ice Skates
    Luogu P4313 文理分科
  • 原文地址:https://www.cnblogs.com/qlky/p/5781016.html
Copyright © 2011-2022 走看看