Codeforces Round #220 (Div. 2)

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毒瘤场.....

A题:,真码农题,直接干爆,枚举,注意越界问题,wa37的看这组数据1 10 1 5 2 2,应该是no

技术分享图片
//#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast,no-stack-protector")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
//#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define pi acos(-1.0)
#define ll long long
#define mod 1000000007
#define C 0.5772156649
#define ls l,m,rt<<1
#define rs m+1,r,rt<<1|1
#define pil pair<int,ll>
#define pii pair<int,int>
#define ull unsigned long long
#define base 1000000000000000000
#define fio ios::sync_with_stdio(false);cin.tie(0)

using namespace std;

const double g=10.0,eps=1e-12;
const int N=1000000+10,maxn=2000+10,inf=0x3f3f3f3f,INF=0x3f3f3f3f3f3f3f3f;


int main()
{
    int n,m,i,j,a,b;
    scanf("%d%d%d%d%d%d",&n,&m,&i,&j,&a,&b);
    int ans1=-1,ans2=-1,ans3=-1,ans4=-1;
    if(abs(i-1)%a==0&&abs(j-1)%b==0&&abs(i-1)/a%2==abs(j-1)/b%2)
    {
        if(abs(j-1)/b!=0&&(1<=i-a||i+a<=n)&&abs(i-1)/a==0)ans1=max(abs(i-1)/a,abs(j-1)/b);
        else if(abs(i-1)/a!=0&&(1<=j-b||j+b<=m)&&abs(j-1)/b!=0)ans1=max(abs(i-1)/a,abs(j-1)/b);
        else if(abs(j-1)/b!=0&&(1<=i-a||i+a<=n)&&abs(i-1)/a!=0&&(1<=j-b||j+b<=m))ans1=max(abs(i-1)/a,abs(j-1)/b);
        else if(abs(i-1)/a==0&&abs(j-1)/b==0)ans1=max(abs(i-1)/a,abs(j-1)/b);
    }
    if(abs(i-1)%a==0&&abs(j-m)%b==0&&abs(i-1)/a%2==abs(j-m)/b%2)
    {
        if(abs(j-m)/b!=0&&(1<=i-a||i+a<=n)&&abs(i-1)/a==0)ans2=max(abs(i-1)/a,abs(j-m)/b);
        else if(abs(i-1)/a!=0&&(1<=j-b||j+b<=m)&&abs(j-m)/b!=0)ans2=max(abs(i-1)/a,abs(j-m)/b);
        else if(abs(j-m)/b!=0&&(1<=i-a||i+a<=n)&&abs(i-1)/a!=0&&(1<=j-b||j+b<=m))ans2=max(abs(i-1)/a,abs(j-m)/b);
        else if(abs(i-1)/a==0&&abs(j-m)/b==0)ans2=max(abs(i-1)/a,abs(j-m)/b);
    }
    if(abs(i-n)%a==0&&abs(j-1)%b==0&&abs(i-n)/a%2==abs(j-1)/b%2)
    {
        if(abs(j-1)/b!=0&&(1<=i-a||i+a<=n)&&abs(i-n)/a==0)ans3=max(abs(i-n)/a,abs(j-1)/b);
        else if(abs(i-n)/a!=0&&(1<=j-b||j+b<=m)&&abs(j-1)/b!=0)ans3=max(abs(i-n)/a,abs(j-1)/b);
        else if(abs(j-1)/b!=0&&(1<=i-a||i+a<=n)&&abs(i-n)/a!=0&&(1<=j-b||j+b<=m))ans3=max(abs(i-n)/a,abs(j-1)/b);
        else if(abs(i-n)/a==0&&abs(j-1)/b==0)ans3=max(abs(i-n)/a,abs(j-1)/b);
    }
    if(abs(i-n)%a==0&&abs(j-m)%b==0&&abs(i-n)/a%2==abs(j-m)/b%2)
    {
        if(abs(j-m)/b!=0&&(1<=i-a||i+a<=n)&&abs(i-n)/a==0)ans4=max(abs(i-n)/a,abs(j-m)/b);
        else if(abs(i-n)/a!=0&&(1<=j-b||j+b<=m)&&abs(j-m)/b!=0)ans4=max(abs(i-n)/a,abs(j-m)/b);
        else if(abs(j-m)/b!=0&&(1<=i-a||i+a<=n)&&abs(i-n)/a!=0&&(1<=j-b||j+b<=m))ans4=max(abs(i-1)/a,abs(j-m)/b);
        else if(abs(i-n)/a==0&&abs(j-m)/b==0)ans4=max(abs(i-n)/a,abs(j-m)/b);
    }
//    printf("%d %d\n",abs(i-n)/a%2,abs(j-m)/b%2);
    if(ans1!=-1||ans2!=-1||ans3!=-1||ans4!=-1)
    {
        int ans=100000000;
        if(ans1!=-1)ans=min(ans,ans1);
        if(ans2!=-1)ans=min(ans,ans2);
        if(ans3!=-1)ans=min(ans,ans3);
        if(ans4!=-1)ans=min(ans,ans4);
        printf("%d\n",ans);
    }
    else puts("Poor Inna and pony!");
    return 0;
}
/********************
3 5 2 2 1 3
********************/
A

B题:日常贪心不会写,xjb写成了dp,还写搓了

题意:找相邻的合成9,要求组出最多的9的方案数;

直接贪心的扫到最远处,类似于72727这样的,然后乘到答案上

技术分享图片
//#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast,no-stack-protector")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
//#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define pi acos(-1.0)
#define ll long long
#define mod 1000000007
#define C 0.5772156649
#define ls l,m,rt<<1
#define rs m+1,r,rt<<1|1
#define pil pair<int,ll>
#define pii pair<int,int>
#define ull unsigned long long
#define base 1000000000000000000
#define fio ios::sync_with_stdio(false);cin.tie(0)

using namespace std;

const double g=10.0,eps=1e-12;
const int N=100000+10,maxn=2000+10,inf=0x3f3f3f3f,INF=0x3f3f3f3f3f3f3f3f;


char s[N];
int main()
{
    scanf("%s",s+1);
    int sz=strlen(s+1);
    ll ans=1,p=1;
    for(int i=2;i<=sz;i++)
    {
        if(s[i]-0+s[i-1]-0==9)p++;
        else
        {
//            printf("%d\n",p);
            if(p!=1&&p%2==1)ans*=(p+1)/2;
            p=1;
        }

    }
//    printf("%d\n",p);
    if(p!=1&&p%2==1)ans*=(p+1)/2;
    printf("%lld\n",ans);
    return 0;
}
/********************

********************/
B

C:有nm的矩阵,找最长的dima,转化成dag上的dp,从d开始dp,然后找能走的最远距离除4就是答案,注意这题要判环,用一个vis标记,-1表示当前正在访问的这一条路,1表示访问过了,0表示没有访问过,如果访问到了一个正在访问的地方,那么就是有环

技术分享图片
//#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast,no-stack-protector")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
//#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define pi acos(-1.0)
#define ll long long
#define mod 1000000007
#define C 0.5772156649
#define ls l,m,rt<<1
#define rs m+1,r,rt<<1|1
#define pil pair<int,ll>
#define pii pair<int,int>
#define ull unsigned long long
#define base 1000000000000000000
#define fio ios::sync_with_stdio(false);cin.tie(0)

using namespace std;

const double g=10.0,eps=1e-9;
const int N=1000+10,maxn=2000+10,inf=0x3f3f3f3f,INF=0x3f3f3f3f3f3f3f3f;

char s[N][N];
int dp[N*N];
int n,m;
int vis[N*N];
vector<int>v[N*N];
int dfs(int u)
{
//    printf("%d\n",u);
    if(dp[u]!=-1)return dp[u];
    dp[u]=1;vis[u]=-1;
    for(int i=0;i<v[u].size();i++)
    {
        int x=v[u][i];
        if(vis[x]<0)
        {
            puts("Poor Inna!");
            exit(0);
        }
        dp[u]=max(dp[u],dfs(x)+1);
    }
    vis[u]=1;
    return dp[u];
}
int main()
{
    scanf("%d%d",&n,&m);
    for(int i=0;i<n;i++)
        scanf("%s",s[i]);
    for(int i=0;i<n;i++)
    {
        for(int j=0;j<m;j++)
        {
            if(s[i][j]==D)
            {
                if(i+1<n&&s[i+1][j]==I)v[i*m+j].pb((i+1)*m+j);
                if(i-1>=0&&s[i-1][j]==I)v[i*m+j].pb((i-1)*m+j);
                if(j+1<m&&s[i][j+1]==I)v[i*m+j].pb(i*m+j+1);
                if(j-1>=0&&s[i][j-1]==I)v[i*m+j].pb(i*m+j-1);
            }
            else if(s[i][j]==I)
            {
                if(i+1<n&&s[i+1][j]==M)v[i*m+j].pb((i+1)*m+j);
                if(i-1>=0&&s[i-1][j]==M)v[i*m+j].pb((i-1)*m+j);
                if(j+1<m&&s[i][j+1]==M)v[i*m+j].pb(i*m+j+1);
                if(j-1>=0&&s[i][j-1]==M)v[i*m+j].pb(i*m+j-1);
            }
            else if(s[i][j]==M)
            {
                if(i+1<n&&s[i+1][j]==A)v[i*m+j].pb((i+1)*m+j);
                if(i-1>=0&&s[i-1][j]==A)v[i*m+j].pb((i-1)*m+j);
                if(j+1<m&&s[i][j+1]==A)v[i*m+j].pb(i*m+j+1);
                if(j-1>=0&&s[i][j-1]==A)v[i*m+j].pb(i*m+j-1);
            }
            else if(s[i][j]==A)
            {
                if(i+1<n&&s[i+1][j]==D)v[i*m+j].pb((i+1)*m+j);
                if(i-1>=0&&s[i-1][j]==D)v[i*m+j].pb((i-1)*m+j);
                if(j+1<m&&s[i][j+1]==D)v[i*m+j].pb(i*m+j+1);
                if(j-1>=0&&s[i][j-1]==D)v[i*m+j].pb(i*m+j-1);
            }
        }
    }
    memset(dp,-1,sizeof dp);
    int ans=0;
    for(int i=0;i<n;i++)
        for(int j=0;j<m;j++)
        {
            int res=dfs(i*m+j);
            if(s[i][j]==D)
                ans=max(ans,res/4);
        }
    if(ans==0)puts("Poor Dima!");
    else printf("%d\n",ans);
    return 0;
}
/********************

********************/
C

D:有一个队列,三种操作,1代表插入1,0代表插入0,-1代表删除下标为a[i]的数,最后输出队列里的数即可

套路题,树状数组维护前缀和,每次删点就在树状数组里的对应地方删点,然后二分找对应在树状数组里的下标

技术分享图片
//#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast,no-stack-protector")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
//#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define pi acos(-1.0)
#define ll long long
#define mod 1000000007
#define C 0.5772156649
#define ls l,m,rt<<1
#define rs m+1,r,rt<<1|1
#define pil pair<int,ll>
#define pii pair<int,int>
#define ull unsigned long long
#define base 1000000000000000000
#define fio ios::sync_with_stdio(false);cin.tie(0)

using namespace std;

const double g=10.0,eps=1e-9;
const int N=1000000+10,maxn=2000+10,inf=0x3f3f3f3f,INF=0x3f3f3f3f3f3f3f3f;

int sum[N],a[N],ans[N];
int cnt;
void add(int i,int v)
{
    while(i<N)
    {
        sum[i]+=v;
        i+=i&(-i);
    }
}
int query(int i)
{
    int ans=0;
    while(i>0)
    {
        ans+=sum[i];
        i-=i&(-i);
    }
    return ans;
}
int change(int x)
{
    int l=0,r=cnt+1;
    while(l<r-1)
    {
        int m=(l+r)>>1;
//        printf("%d %d\n",m,query(m));
        if(query(m)<x)l=m;
        else r=m;
    }
    if(query(r)<x)return -1;
    return r;
}
int main()
{
    int n,m;
    scanf("%d%d",&n,&m);
    for(int i=1;i<=m;i++)scanf("%d",&a[i]);
    cnt=1;
    for(int i=0;i<n;i++)
    {
        int x;
        scanf("%d",&x);
        if(x==-1)
        {
            vector<int>v;
            for(int j=1;j<=m;j++)
            {
                int pos=change(a[j]);
//                printf("###%d!!!\n",pos);
                if(pos==-1)break;
                v.pb(pos);
            }
            for(int i=0;i<v.size();i++)
                add(v[i],-1);
        }
        else
        {
            add(cnt,1);
            ans[cnt++]=x;
        }
    }
//    printf("%d\n",change(1));
    if(change(1)==-1)return 0*puts("Poor stack!");
    for(int i=1;;i++)
    {
        int pos=change(i);
        if(pos==-1)break;
        printf("%d",ans[pos]);
    }
    return 0;
}
/********************

********************/
D

 

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