ssl提高组周二备考赛【2018.10.30】

版权声明：原创，未经作者允许禁止转载 https://blog.csdn.net/Mr_wuyongcong/article/details/83541563

前言

依旧想去德育基地…

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成绩

$Rank$	$Person$	$Score$	$A$	$B$	$C$
$1$	$2017xxy$	$210$	$40$	$100$	$70$
$2$	$2017myself$	$190$	$20$	$100$	$70$
$3$	$2017lxf$	$180$	$0$	$90$	$90$
$4$	$2017zyc$	$170$	$0$	$100$	$70$
$5$	$2017zyx$	$150$	$40$	$60$	$50$
$6$	$2017xjq$	$130$	$0$	$100$	$30$
$7$	$2017lrz$	$100$	$10$	$90$	$0$
$7$	$2013lyk$	$100$	$0$	$100$	$0$
$9$	$2015zyf$	$90$	$20$	$0$	$70$
$10$	$2013lxh$	$90$	$0$	$90$	$0$

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正题

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$T1:nssl1254-A($林下风气 $)$【树形 $dp$】

博客链接:
https://blog.csdn.net/Mr_wuyongcong/article/details/83541098

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$T2:nssl1255-B($轻功 $)$【 $SPFA,$分层图】

博客链接:
https://blog.csdn.net/Mr_wuyongcong/article/details/83541258

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$T3:nssl1256-C($盟主的忧虑 $)$【并查集】

博客链接:
https://blog.csdn.net/Mr_wuyongcong/article/details/83541476

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$some\ of\ code$

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T2 20分code

#include<cstdio>
#include<cstring>
#include<algorithm>
#define N 4000
#define XJQ 19260817
using namespace std;
struct node{
	int to,next;
}a[N];
int ls[N],w[N],maxs,mins,ans,n,k,tot,x,y,in[N];
void addl(int x,int y)
{
	a[++tot].to=y;
	a[tot].next=ls[x];
	ls[x]=tot;
}
void dp1()
{
	for(int i=1;i<=n;i++)
	{
		maxs=0;
		mins=2147483647;
		for(int j=i;j<=n;j++)
		{
			maxs=max(maxs,w[j]);
			mins=min(mins,w[j]);
			if(maxs-mins==k) ans++;
		}
	}
	printf("%d",ans);
}
int main()
{
	scanf("%d%d",&n,&k);
	for(int i=1;i<=n;i++)
	    scanf("%d",&w[i]);
	for(int i=1;i<n;i++)
	{
	    scanf("%d%d",&x,&y);
	    addl(x,y);addl(y,x);
	    in[x]++;in[y]++;
	    maxs=max(maxs,max(in[x],in[y]));
	}
	if(maxs<=2)
		dp1();
	else printf("0");
}

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T3 70分code

#include<cstdio>
#include<algorithm>
#define N 100010
using namespace std;
struct node{
	int to,w,next,from;
}a[N];
int ls[N],tot,x,y,w,ans,dep[N],n,m,S,dfn[N],end[N],cnt;
void addl(int x,int y,int w)
{
	a[++tot].to=y;a[tot].w=w;
	a[tot].next=ls[x];ls[x]=tot;
	a[tot].from=x;
}
void dfs(int x,int fa)
{
	dfn[x]=++cnt;
	dep[x]=dep[fa]+1;
	for(int i=ls[x];i;i=a[i].next)
	  if(i<S)
	  {
		  int y=a[i].to;
		  if(y==fa) continue;
		  dfs(y,x);
	  }
	end[x]=cnt;
}
bool cmp(node x,node y)
{return x.from<y.from;}
int next(int x)
{
	while(dep[a[x].from]>dep[a[x].to]) x++;
	return x;
}
int main()
{
	scanf("%d%d",&n,&m);
	for(int i=1;i<n;i++)
	{
		scanf("%d%d",&x,&y);
		addl(x,y,0);
		addl(y,x,0);
	}
	S=tot+1;
	for(int i=1;i<=m;i++)
	{
		scanf("%d%d%d",&x,&y,&w);
		addl(x,y,w);
	}
	dfs(1,0);
	for(int i=1;i<S;i+=2)
	{
		ans=2147483647;
		int x=a[i].to;
		if(dep[a[i].to]<dep[a[i+1].to]) x=a[i+1].to;
	    for(int j=S;j<=tot;j++)
	      if(dfn[a[j].to]>=dfn[x]&&dfn[a[j].to]<=end[x]&&
		  (dfn[a[j].from]<dfn[x]||dfn[a[j].from]>end[x])
		  ||
			dfn[a[j].from]>=dfn[x]&&dfn[a[j].from]<=end[x]&&
		  (dfn[a[j].to]<dfn[x]||dfn[a[j].to]>end[x]))
	           ans=min(ans,a[j].w);
	    if(ans==2147483647) printf("-1\n");
	    else printf("%d\n",ans);
	}
}

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尾声

话说题目又ABC。老师改题面了