Test 6 for NOIP

头大

这个暑假完就要去搞NOIP了。。。

暑假55天也就20次测试。。。为防万一我还是每次测试玩都写个总结。。

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？？？曾老说好的题为什么做了一个半小时又换题了系列？？？
。。。这次更无语。。中途一群人闹着换题被搞晕然后心态失衡零分。

Day？（0/300）

T1 T1：排列的最大长度

自己不背最长子序列模板怪我咯

STD.CPP

#include<iostream>#include<cstdio>#include<algorithm>#include<cmath>#include<cstdlib>#include<string>#include<cstring>#include<ctime>using namespace std;int n,input[100005],b[100005];int a,f[100005];int main(){    cin >> n;    for(int i=1;i<=n;i++)cin>>a,input[a]=i;    for(int i=1;i<=n;i++)cin>>a,b[i]=input[a];    int l=1,r=0,top=0;    for(int i=1;i<=n;i++)    {        l = 1;   r = top;        int mid = (l+r)/2;        while(l<=r)        {            mid = (l+r)/2;            if(f[mid]>b[i]) r = mid-1;            else l = mid+1;        }        if(l>top)   top++,l=top;        f[l] = b[i];    }    cout << top;}

T2 T2：覆盖节点

当时没读懂题就没做。。事后发现并不难想。。

STD.CPP

#include<cstdio>#include<cstdlib>#include<iostream>#include<iomanip>#include<cstring>#include<string>#include<algorithm>#include<ctime>using namespace std;int n,l,tot=0,first[2000002];int stack[2000002];bool visit[2000002];struct node{    int x;    int y;    int w;    int next;}side[2000002];int d[1000005];void addedge(int x,int y,int w){    side[++tot].x=x;    side[tot].y=y;    side[tot].w=w;    side[tot].next=first[x];    first[x]=tot;    d[x] += 1;}int main() {    //freopen("t2.in","r",stdin);    //freopen("t2.out","w",stdout);     cin.sync_with_stdio(false);    int x,y;        cin >> n >> l;    l *= 2;    if(2*n==l)  {cout << n;return 0;}    for(int i=1;i<n;i++)    {        cin >> x >> y;        addedge(x,y,1);        addedge(y,x,1);    }    int l1=1,r1=0;    for(int i=1;i<=n;i++)      if(d[i]==1)      {        r1 += 1;    stack[r1] = i;        visit[i] = true;      }    int ans = 0;    while(l1<=r1)    {        int k = r1-l1+1;        ans += min(l,k);        for(int j=1;j<=k;j++)          for(int i=first[stack[l1++]];i;i=side[i].next)          {            d[side[i].y]--;            if(!visit[side[i].y]&&d[side[i].y]==1)            {                stack[++r1] = side[i].y;                visit[side[i].y] = true;            }          }    }    cout << ans;    }

T3 T3：系列维护

果断：当时还不会树状数组暴力又挂。。。还得研究研究

STD.CPP

#include<iostream>#include<algorithm>#include<cstdio>#include<cstdlib>#include<cmath>#include<ctime>#include<cstring>#include<string>using namespace std;inline void readi(int &i){    char p;    p=getchar();    while(p>'9'||p<'0')p=getchar();    while(p>='0'&&p<='9')    {        i=i*10+p-'0';        p=getchar();    }}int m,n,size,us[1000005],s[1000005],c[1000005],a[1000005];long long num,small,sum,tr2[1000005];bool bz[1000005];char ch;int tr1[1000005];inline int lowbit(int i){    return i&(-i);}inline void add(int x,int y){    int i=x;    while(i<=size)    {        tr1[i]+=y;        tr2[i]+=us[x]*y;        i+=lowbit(i);    }}inline void query(int x){    sum=0;    small=0;    while(x)    {        sum+=tr1[x];        small+=tr2[x];        x-=lowbit(x);    }}int main(){    //freopen("1.in","r",stdin);    readi(n);    readi(m);    for(int i=1;i<=m;i++)    {        ch=getchar();        while(ch!='Z'&&ch!='U')ch=getchar();        if(ch=='Z')bz[i]=1;        readi(c[i]);        readi(s[i]);        us[++size]=s[i];    }    sort(us+1,us+size+1);    size=unique(us+1,us+size+1)-us-1;    for(int i=1;i<=m;i++)        s[i]=lower_bound(us+1,us+size+1,s[i])-us;    for(int i=1;i<=m;i++)        if(bz[i])        {            query(s[i]);            sum=num-sum;            if(small>=(long long)1*us[s[i]]*(c[i]-sum))puts("Yes");            else puts("No");        }        else        {            if(a[c[i]])add(a[c[i]],-1);            else num++;            add(s[i],1);            a[c[i]]=s[i];        }    return 0;}

还是一句话：多刷题。。。

彩蛋？

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