NOIP模拟10.22

2014提高D2
A.无线网络发射器选址 暴力枚举选在哪即可。AC
B.寻找道路 图论+bfs+spfa AC
C.解方程 数论+筛法+枚举。 脑残没想到取模，去写高精度，结果当然是挂了。只拿了30.具体题解见这里

A

#include <bits/stdc++.h>using namespace std;#define N 30#define inf 0x3f3f3f3f#define ll long longinline int read(){    int x=0,f=1;char ch=getchar();    while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}    while(ch>='0'&&ch<='9') x=x*10+ch-'0',ch=getchar();    return x*f;}int d,n,x[N],y[N],val[N],ans=0,cnt=0;int main(){//  freopen("a.in","r",stdin);    d=read();n=read();    for(int i=1;i<=n;++i) x[i]=read(),y[i]=read(),val[i]=read();    for(int i=0;i<=128;++i)        for(int j=0;j<=128;++j){            int x1=max(0,i-d),x2=min(128,i+d),y1=max(0,j-d),y2=min(128,j+d);            int res=0;            for(int k=1;k<=n;++k)                if(x[k]>=x1&&x[k]<=x2&&y[k]>=y1&&y[k]<=y2) res+=val[k];            if(res>ans) ans=res,cnt=1;else if(res==ans) cnt++;        }    printf("%d %d\n",cnt,ans);    return 0;}

B

#include <bits/stdc++.h>using namespace std;#define N 10010#define inf 0x3f3f3f3f#define ll long long#define M 200010inline int read(){    int x=0,f=1;char ch=getchar();    while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}    while(ch>='0'&&ch<='9') x=x*10+ch-'0',ch=getchar();    return x*f;}int n,m,s,t,h[N],num=0,h1[N],d[N];bool f[N],bad[N],inq[N];//f[i]--i能否到t,bad[i]--i能否在路径上 struct edge{    int to,next;}data1[M],data[M];inline void add(int x,int y){    data[++num].to=y;data[num].next=h[x];h[x]=num;    data1[num].to=x;data1[num].next=h1[y];h1[y]=num;}void bfs(int ss){    queue<int>q;q.push(ss);f[ss]=1;    while(!q.empty()){        int x=q.front();q.pop();        for(int i=h1[x];i;i=data1[i].next){            int y=data1[i].to;if(!f[y]) f[y]=1,q.push(y);        }    }}void spfa(){    queue<int>q;memset(d,inf,sizeof(d));    q.push(s);d[s]=0;inq[s]=1;    while(!q.empty()){        int x=q.front();q.pop();inq[x]=0;        for(int i=h[x];i;i=data[i].next){            int y=data[i].to;            if(d[y]>d[x]+1){                d[y]=d[x]+1;if(!inq[y]) inq[y]=1,q.push(y);            }        }    }}int main(){//  freopen("b.in","r",stdin);    n=read();m=read();    while(m--){        int x=read(),y=read();if(x==y) continue;add(x,y);    }s=read();t=read();bfs(t);    for(int x=1;x<=n;++x)        for(int i=h[x];i;i=data[i].next){            int y=data[i].to;if(!f[y]){bad[x]=1;break;}        }m=num;num=0;memset(h,0,sizeof(h));     for(int x=1;x<=n;++x){        if(bad[x]) continue;        for(int i=h1[x];i;i=data1[i].next){            int y=data1[i].to;if(bad[y]) continue;            data[++num].to=x;data[num].next=h[y];h[y]=num;        }    }spfa();    if(d[t]==inf) puts("-1");    else printf("%d\n",d[t]);    return 0;}

C

#include <bits/stdc++.h>using namespace std;#define N 110#define inf 0x3f3f3f3f#define ll long longinline int read(){    int x=0,f=1;char ch=getchar();    while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}    while(ch>='0'&&ch<='9') x=x*10+ch-'0',ch=getchar();    return x*f;}int n,m,prime[3]={10007,10917,30071},a[N][3];bool f[40000][3];char s[10010];vector<int>ans;bool calc(int x,int j){    int tmp=a[n][j];    for(int i=n-1;i>=0;--i)        tmp=(tmp*x+a[i][j])%prime[j];    return !tmp;}int main(){//  freopen("a.in","r",stdin);    n=read();m=read();    for(int i=0;i<=n;++i){        scanf("%s",s+1);int len=strlen(s+1);        for(int j=0;j<3;++j){            if(s[1]=='-'){                int x=0;                for(int ii=2;ii<=len;++ii)                    x=x*10+s[ii]-'0',x%=prime[j];                a[i][j]=-x;            }else{                int x=0;                for(int ii=1;ii<=len;++ii)                    x=x*10+s[ii]-'0',x%=prime[j];                a[i][j]=x;            }        }           }    for(int j=0;j<3;++j)        for(int i=0;i<prime[j];++i)            f[i][j]=calc(i,j);    for(int i=1;i<=m;++i){        bool flag=1;        for(int j=0;j<3;++j)            if(!f[i%prime[j]][j]) flag=0;        if(flag) ans.push_back(i);    }    printf("%d\n",ans.size());    for(int i=0;i<ans.size();++i) printf("%d\n",ans[i]);    return 0;}