Codeforces Beta Round #5

Codeforces Beta Round #5

http://codeforces.com/contest/5

A

模拟题

#include<bits/stdc++.h>
using namespace std;
#define lson l,mid,rt<<1
#define rson mid+1,r,rt<<1|1
#define sqr(x) ((x)*(x))
typedef long long ll;
/*#ifndef ONLINE_JUDGE
        freopen("1.txt","r",stdin);
#endif */


int main(){
    std::ios::sync_with_stdio(false);
    #ifndef ONLINE_JUDGE
        freopen("1.txt","r",stdin);
    #endif
    set<string>se;
    string str;
    int i;
    int ans=0;
    while(getline(cin,str)){
        if(str.length()==0) break;
        if(str[0]=='+'||str[0]=='-'){
            if(str[0]=='+'){
                str=str.substr(1);
                se.insert(str);
            }
            else{
                str=str.substr(1);
                se.erase(str);
            }
        }
        else{
            for(i=0;i<str.length();i++){
                if(str[i]==':') break;
            }
           // cout<<i<<endl;
            ans+=se.size()*(str.length()-1-i);
        }
    }
    cout<<ans<<endl;
    return 0;
}

B

画图题

#include<bits/stdc++.h>
using namespace std;
#define lson l,mid,rt<<1
#define rson mid+1,r,rt<<1|1
#define sqr(x) ((x)*(x))
typedef long long ll;
/*#ifndef ONLINE_JUDGE
        freopen("1.txt","r",stdin);
#endif */
string str[1005];

int main(){
    std::ios::sync_with_stdio(false);
    #ifndef ONLINE_JUDGE
        freopen("1.txt","r",stdin);
    #endif
    int n=0;
    while(getline(cin,str[n++]));
    int Max=0;
    n--;
    for(int i=0;i<n;i++){
        int len=str[i].length();
        Max=max(Max,len);
    }
    for(int i=0;i<Max+2;i++){
        cout<<'*';
    }
    cout<<endl;
    int cc=1;
    for(int i=0;i<n;i++){
        cout<<'*';
        int k=Max-str[i].length();
        int tou=k/2;
        int wei=k/2;
        k=k-wei-tou;
        if(k){
            if(cc%2) wei++,cc++;
            else tou++,cc++;
        }
        for(int j=0;j<tou;j++) cout<<' ';
        cout<<str[i];
        for(int j=0;j<wei;j++) cout<<' ';
        cout<<'*'<<endl;
    }
    for(int i=0;i<Max+2;i++){
        cout<<'*';
    }
    cout<<endl;
    return 0;
}

C

找到匹配最大字符串，直接暴力模拟

#include<bits/stdc++.h>
using namespace std;
#define lson l,mid,rt<<1
#define rson mid+1,r,rt<<1|1
#define sqr(x) ((x)*(x))
typedef long long ll;
/*#ifndef ONLINE_JUDGE
        freopen("1.txt","r",stdin);
#endif */

int a[1000005];
int len[1000005];

int main(){
    std::ios::sync_with_stdio(false);
    #ifndef ONLINE_JUDGE
        freopen("1.txt","r",stdin);
    #endif
    string str;
    cin>>str;
    stack<int>st;
    /// () (()) ()
    memset(a,-1,sizeof(a));
    for(int i=0;i<str.length();i++){
        if(str[i]=='('){
            st.push(i);
        }
        else{
            if(st.empty()){
                continue;
            }
            else{
                a[i]=st.top();
                st.pop();
            }
        }
    }
    int Max=0,num=0;
    for(int i=0;i<str.length();i++){
        if(a[i]!=-1){
            len[i]=(a[i]>0?len[a[i]-1]:0)+i-a[i]+1;
            if(Max<len[i]){
                Max=len[i];
                num=1;
            }
            else if(Max==len[i]) num++;
        }
    }


    if(!Max) cout<<"0 1"<<endl;
    else{
        cout<<Max<<" "<<num<<endl;
    }
    return 0;
}

D

物理题

#include<bits/stdc++.h>
using namespace std;
#define lson l,mid,rt<<1
#define rson mid+1,r,rt<<1|1
#define sqr(x) ((x)*(x))
typedef long long ll;
/*#ifndef ONLINE_JUDGE
        freopen("1.txt","r",stdin);
#endif */
double a,v,l,d,w,ans,t1,t2,t3,x1,x2,x3;
int flag;

int main(){
    scanf("%lf%lf",&a,&v);
    scanf("%lf%lf%lf",&l,&d,&w);
    t1=v/a;
    x1=a*t1*t1/2;
    if(w<v)
        flag=1;
    if(flag==1){
        t2=w/a;
        x2=a*t2*t2/2;
        if(x2<d){
            t3=(v-w)/a;
            x3=w*t3+a*t3*t3/2;
            if(x1+x3<d)
                ans=t1+t3+(d-x1-x3)/v;
            else
                ans=t2+2*(sqrt(a*(d-x2)+w*w)-w)/a;
            if(x3<l-d)
                ans+=t3+(l-d-x3)/v;
            else
                ans+=(sqrt(2*a*(l-d)+w*w)-w)/a;
        }
        else
            flag=0;
    }
    if(flag==0){
        if(x1<l)
            ans=t1+(l-x1)/v;
        else
            ans=sqrt(2*l/a);
    }
    printf("%.6f
",ans);
    return 0;
}

E

首先我们把环变成一个链，然后用一个并查集的思想，处理每一座山左边第一个比这个山高的山是哪个，右边第一个比这个山高的是哪个，这个区域内和这个山高度一样的山有多少

然后跑一发并查集就好了

#include<bits/stdc++.h>
using namespace std;
#define lson l,mid,rt<<1
#define rson mid+1,r,rt<<1|1
#define sqr(x) ((x)*(x))
#define maxn 1000010
typedef long long ll;
/*#ifndef ONLINE_JUDGE
        freopen("1.txt","r",stdin);
#endif */

int a[maxn];
int b[maxn];
int l[maxn];
int r[maxn];
int k[maxn];
int main()
{
    int n;
    cin>>n;
    int p=-1;
    for(int i=0;i<n;i++)
    {
        cin>>a[i];
        if(p==-1)
            p=i;
        else if(a[i]>a[p])
        {
            p=i;
        }
    }
    for(int i=0;i<n;i++)
        b[i]=a[(i+p+n)%n];
    b[n]=a[p];
    for(int i=1;i<n;i++)
    {
        l[i]=i-1;
        while(l[i]>0&&b[i]>=b[l[i]])
            l[i]=l[l[i]];
    }
    k[n]=0;
    for(int i=n-1;i>=0;i--)
    {
        r[i]=i+1;
        while(r[i]<n&&b[i]>b[r[i]])
            r[i]=r[r[i]];
        if(r[i]<n&&b[i]==b[r[i]])
        {
            k[i]=k[r[i]]+1;
            r[i]=r[r[i]];
        }
    }
    ll ans=0;
    for(int i=1;i<n;i++)
    {
        ans+=k[i];
        ans+=1;
        if(l[i]!=0||r[i]!=n)
            ans++;
    }
    cout<<ans<<endl;
}

https://paste.ubuntu.com/p/vyCmrdSsXj/