比赛 ZLXOI2015Day2 评测结果 AAAAAAAAAA
题目名称 ZLX的陨落 最终得分 100
用户昵称 ifAandBisC 运行时间 0.889 s
代码语言 C++ 内存使用 60.04 MiB
提交时间 2015-10-30 20:28:57
显示代码纯文本
#include<iostream>
#include<cstring>
#include<cstdio>
#include<vector>
#include<cmath>
#define iii 1010101

using namespace std;
int n;
int dis[iii],f[iii],ans[iii];
bool vis[iii],flag[iii];
vector<int> head[iii];
vector<int> val [iii];
vector<int> Qus[iii];
vector<int> num[iii];

int find (int x){if (x!=f[x])return f[x]=find(f[x]);return x;}
void add (int a,int b,int c)
{
	head[a].push_back(b);
	val [a].push_back(c);
}
void Lca (int T)
{
	vis[T]=true;
	int len=head[T].size();
	for (int i=0;i<len;i++)
	if (!vis[head[T][i]])
	{
		dis[head[T][i]]=dis[T]+val[T][i];
		Lca (head[T][i]);
		flag[head[T][i]]=true;
		f[head[T][i]]=T;
	}
	len=Qus[T].size();
	for (int i=0;i<len;i++)
	if (flag[Qus[T][i]])
	{
		int C=find(Qus[T][i]);
		ans[num[T][i]]=dis[Qus[T][i]]+dis[T]-2*dis[C];
	}
}
int main ()
{
	freopen ("ThefallingofZLX.in","r",stdin);
	freopen ("ThefallingofZLX.out","w",stdout);
	memset (vis, 0,sizeof(vis));
	memset (flag,0,sizeof(flag));
	int m,q,a,b,c,t=0x7fffffff;
	scanf ("%d%d",&n,&m);
	for (int i=1;i<=m;i++)
	{
		scanf ("%d%d%d",&a,&b,&c);
		add (a,b,c);
		add (b,a,c);
		t=min(t,min(a,b));
	}
	scanf ("%d",&q);
	for (int i=1;i<=q;i++)
	{
		scanf ("%d%d",&a,&b);
		Qus[a].push_back(b);
		Qus[b].push_back(a);
		num[a].push_back(i);
		num[b].push_back(i);
	}
	for (int i=1;i<=n;i++) f[i]=i;
	dis[t]=0;
	Lca (t);
	for (int i=1;i<=q;i++)
		printf ("%d\n",ans[i]);
	return 0;
}