noip2014总结

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原创最新推荐文章于 2026-03-04 04:32:04 发布 980 阅读 AI 写同款· GEO 优化 ›

1、Ovirt 开源虚拟化平台安装 Ovirt虚拟化Node和Engine安装阅读详情

终于有时间来总结一下noip2014了。。。。。。

蒟蒻360 SD 并列rank 76(无限仰慕fye神,TA神，Rivendell神。。。)

总结一下:

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Day1 T1,Day2 T2 水题两道，要做到又好又快。。。 code:

#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;
int a[201],b[201],n,na,nb;
int main()
{
    int i,sca,scb;
    freopen("rps.in","r",stdin);
    freopen("rps.out","w",stdout);
    memset(a,0,sizeof(a)); memset(b,0,sizeof(b));
    scanf("%d%d%d",&n,&na,&nb);
    for (i=1;i<=na;++i)
      scanf("%d",&a[i]);
    for (i=na+1;i<=n;++i)
      a[i]=a[(i-1)%na+1];
    for (i=1;i<=nb;++i)
      scanf("%d",&b[i]);
    for (i=nb+1;i<=n;++i)
      b[i]=b[(i-1)%nb+1];
    sca=0; scb=0;
    for (i=1;i<=n;++i)
      {
        if (a[i]==0)
          {
            if ((b[i]==2)||(b[i]==3))
              sca++;
            if ((b[i]==1)||(b[i]==4))
              scb++;
          }
        if (a[i]==1)
          {
            if ((b[i]==0)||(b[i]==3))
              sca++;
            if ((b[i]==2)||(b[i]==4))
              scb++;
          }
        if (a[i]==2)
          {
            if ((b[i]==1)||(b[i]==4))
              sca++;
            if ((b[i]==0)||(b[i]==3))
              scb++;
          }
        if (a[i]==3)
          {
            if ((b[i]==2)||(b[i]==4))
              sca++;
            if ((b[i]==0)||(b[i]==1))
              scb++;
          }
        if (a[i]==4)
          {
            if ((b[i]==0)||(b[i]==1))
              sca++;
            if ((b[i]==2)||(b[i]==3))
              scb++;
          }
      }
    printf("%d %d\n",sca,scb);
    fclose(stdin); fclose(stdout);
    return 0;
}

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
int map[200][200];
int maxn,maxi,d,n;
int main()
{
    int i,j,x,y,k,m,ans;
    freopen("wireless.in","r",stdin);
    freopen("wireless.out","w",stdout);
    scanf("%d",&d);
    memset(map,0,sizeof(map));
    scanf("%d",&n);
    for (i=1;i<=n;++i)
      {
        scanf("%d%d%d",&x,&y,&k);
        map[x][y]=k;
      }
    maxn=0; maxi=0;
    for (i=0;i<=128;++i)
      for (j=0;j<=128;++j)
        {
          ans=0;
          for (k=max(0,i-d);k<=min(128,i+d);++k)
            for (m=max(0,j-d);m<=min(128,j+d);++m)
              ans+=map[k][m];
          if (ans==maxn)
            maxi++;
          if (ans>maxn)
            {maxn=ans; maxi=1;}
        }
    printf("%d %d\n",maxi,maxn);
    fclose(stdin); fclose(stdout);
    return 0;
}

link树形DP，但需要一些小技巧，DFS建树，穷举中间节点，处理同层和上下两层（考试想简单了，60）AC CODE:

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
int next[500000],point[250000];
int a[250000]={0},n,ans,maxn;
int e[500000];
void treedp(int now,int last,int lastest,int sum)
{
	int j,c,maxf,maxs;
	ans=(ans+(a[now]*sum)%10007+(a[now]*a[lastest])%10007)%10007;
	maxn=max(maxn,a[now]*a[lastest]);
	j=point[now]; c=0; maxs=maxf=0;
	while (j!=0)
	  {
	    if (e[j]!=last)
	      {
	      	treedp(e[j],now,last,c);
	        c=(c+a[e[j]])%10007;
	        if (a[e[j]]<=maxf&&a[e[j]]>maxs) maxs=a[e[j]];
	        if (a[e[j]]>maxf) {maxs=maxf; maxf=a[e[j]];}
		  }   
	    j=next[j];
      }
	maxn=max(maxn,maxf*maxs);
}
int main()
{
	int i,x,y;
	freopen("linkb.in","r",stdin);
	freopen("linkb.out","w",stdout);
	memset(next,0,sizeof(next));
	memset(point,0,sizeof(point));
	scanf("%d",&n);
	for (i=1;i<=n-1;++i)
	  {
	    scanf("%d%d",&x,&y); 
	    next[i*2-1]=point[x]; point[x]=i*2-1;
		next[i*2]=point[y]; point[y]=i*2;
		e[i*2-1]=y; e[i*2]=x; 
	  }
	for (i=1;i<=n;++i)
	  scanf("%d",&a[i]);
	ans=0; maxn=0;
	treedp(1,0,0,0);
	ans=(ans*2)%10007;
	printf("%d %d",maxn,ans);
	fclose(stdin); fclose(stdout);
}

road更简单，dfs判“连通”（考试竟然用floyed..... 60),跑一遍spfa即可 AC CODE:

#include<iostream>
#include<cstdio>
#include<cstring> 
using namespace std;
struct hp{
	int u,v;
}a[200001];
int queue[100001],s,t,dis[100001]; 
int next1[200001],point1[100001],next2[200001],point2[100001],n,m;
bool f[100001],ff[100001];
void floodfill(int i)
{
	int j;
	f[i]=true; j=point1[i]; 
	while (j!=0)
	  {
	  	if (f[a[j].v]==false)
	      floodfill(a[j].v);
	    j=next1[j];
	  }
}
int spfa() 
{
	int head,tail,i,now,vi,y;
	memset(queue,0,sizeof(queue));
	memset(dis,127,sizeof(dis)); 
	memset(f,false,sizeof(f)); 
	head=0; tail=1; queue[tail]=s; y=dis[0];
	dis[s]=0; f[s]=true;
	while (head!=tail)
	  {
	    head=head%100000+1;
	    now=queue[head];
	    f[now]=false;
	    i=point2[now];
	    while (i!=0)
	      {
	        vi=a[i].u;
	        if (ff[vi]&&dis[vi]>dis[now]+1)
	          {
	            dis[vi]=dis[now]+1;
	            if (f[vi]==false)
	              {
	                f[vi]=true; tail=tail%100000+1;
	                queue[tail]=vi;
	              }
	          }
	        i=next2[i];
	      }
      }
	if (dis[t]>=y) return -1;
	else return dis[t]; 
}
int main()
{
	int j,i,x,y;
	bool d;
	freopen("roadb.in","r",stdin); freopen("roadb.out","w",stdout);
	scanf("%d%d",&n,&m);
	memset(next1,0,sizeof(next1));
	memset(point1,0,sizeof(point2));
	memset(next2,0,sizeof(next1));
	memset(point2,0,sizeof(point2));
	memset(f,false,sizeof(f)); memset(ff,false,sizeof(ff)); 
	for (i=1;i<=m;++i)
	  {
	    scanf("%d%d",&x,&y);
	    next1[i]=point1[y]; point1[y]=i;
	    next2[i]=point2[x]; point2[x]=i;
	    a[i].v=x; a[i].u=y;
	  }
	scanf("%d%d",&s,&t);  floodfill(t); 
	for (i=1;i<=n;++i)
	  {
	    d=f[i];
		j=point2[i];
		while (j!=0)
		  {
		    d=d&&f[a[j].u];
		    j=next2[j];
	      }
	    ff[i]=d;
	  }
	printf("%d\n",spfa());
	fclose(stdin); fclose(stdout);
}

Day1 T3完全背包,Day2 T3各种乱搞代码未写。。。。。。

1.加强对动归的练习 2.多了解一些数论知识 3.要建立起合适的数学模型，力求降低时间复杂度（前提是算对大O......)

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