东北大学acm第一周周赛

#include<bits/stdc++.h>
using namespace std;
const int N=1005;
int a[N],n;
char c;
int main(){
	cin>>n;
	c=getchar();
	for(int i=1;i<=n;++i){
		c=getchar();
		if(c=='L'){
			a[i]=2;
			if(!a[i-1]){
				a[i-1]=1;
			}
			if(!a[i+1]){
				a[i+1]=1;
			}
		}
	}
	for(int i=1;i<=n;++i){
		if(!a[i]){
			cout<<"C";
		}else if(a[i]==1){
			cout<<".";
		}else{
			cout<<"L";
		}
	} 
}

#include<bits/stdc++.h>
using namespace std;
const int N=1200;
string s;
int num1[N],num2[N],ans[2*N];
char print[]={'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};
int read(int a[]){
	cin>>s;
	int n=s.length();
	for(int i=0;i<n;++i){
		if(isdigit(s[n-i-1])){
			a[i]=s[n-i-1]-'0';
		}else{
			a[i]=s[n-i-1]-'A'+10;
		}
	}
	return n;
}
int main(){
	int len1=read(num1);
	int len2=read(num2);
	int len3=2*N-1;
	for(int i=0;i<len1;++i){
		for(int j=0;j<len2;++j){
			ans[i+j]+=num1[i]*num2[j];
		}
	}
	for(int i=0;i<=len3;++i){
		if(ans[i]>=16){
			ans[i+1]+=ans[i]/16;
			ans[i]%=16;
		}
	}
	while(ans[len3]==0&&len3>0){
		--len3;
	}
	for(int i=len3;i>=0;--i){
		cout<<print[ans[i]];
	}
}

#include <bits/stdc++.h>
using namespace std;
const int N=1e6+5;
int n,m,ans,dis[N];
bool check(int x){
    int t=max(dis[1]-m,0);  
    for(int i=2;i<=n;++i){
        t+=x; 
        if(dis[i]-t>m)  
            t=dis[i]-m;
        if(dis[i]-t<0) 
            return false;
    }
    return true;
}
int main(){
    cin>>n>>m;
    for(int i=1;i<=n;++i)
        cin>>dis[i];
    sort(dis+1,dis+n+1);
    int L=1,R=dis[n];
    while(L<=R){
        int M=(L+R)>>1;
        if(check(M)){
            ans=M;
            L=M+1;
        }
        else
         R=M-1;
    }
    cout<<ans<<endl;
}

#include<bits/stdc++.h>
using namespace std;
const int N=1e5+5;
struct node{
	string index,next;
	int num;
}Node[N];
string nxt;
int n,m;
map<string,pair<int,string>>mp;
int main(){
	cin>>nxt>>n>>m; 
	for(int i=1;i<=n;++i){
		cin>>Node[i].index>>Node[i].num>>Node[i].next;
		mp[Node[i].index]={Node[i].num,Node[i].next};
	}
	for(int i=1;i<=n;++i){
		Node[i].index=nxt;
		Node[i].num=mp[Node[i].index].first;
		nxt=Node[i].next=mp[Node[i].index].second;
		if(nxt=="-1"){
			n=i;break;
		}
	}
	for(int i=1;i<=n;++i){
		if(!(i%m)){
			int l=i-m+1,r=i;
			while(l<r){
				swap(Node[l],Node[r]);
				++l,--r;
			}
		}
	}
	for(int i=1;i<=n;++i){
		cout<<Node[i].index<<" "<<Node[i].num;
		if(i!=n){
			cout<<" "<<Node[i+1].index<<endl;
		}else{
			cout<<" "<<"-1"<<endl;
		}
	}
} 

#include<bits/stdc++.h>
using namespace std;
double T,a[6];
double eps=1e-7;
double f(double x){
	double ans=0;
	for(int i=0;i<4;++i){
		ans=ans*x+a[i];
	}
	return ans;
}
int main(){
	cin>>T;
	while(T--){
		for(int i=0;i<6;++i){
			cin>>a[i];
		}
		int cnt=0;
		for(int i=a[4];i<=a[5];++i){
			double l1=i,l2=i+1;
			if(f(l1)==0){
				if(cnt) cout<<" ";
				printf("%.6f",l1);
				cnt++;
			}else if(f(l1)*f(l2)<0){
				while(l2-l1>=eps){
					double mid=(l1+l2)/2;
					if(f(mid)*f(l1)<=0){
						l2=mid;
					}else{
						l1=mid;
					}
				}
				if(cnt) cout<<" ";
				printf("%.6f",l1);
				cnt++;
			}
			if(cnt==3) break;
		}
		cout<<endl;
	}
}