8 solutions

  • 1
    @ 2022-4-25 22:05:53

    用数组模拟

    #include<bits/stdc++.h>
    using namespace std;
    const int N=1e6+7;
    int n,p[N];
    vector<int>erro;
    int pl=N/2,pr=N/2-1;
    int main(){
    	cin>>n;
    	string op;
    	int x;
    	for(int i=1;i<=n;i++){
    		cin>>op;
    		if(op=="LIN"){
    			cin>>x;
    			p[--pl]=x;
    		}else if(op=="RIN"){
    			cin>>x;
    			p[++pr]=x;
    		}else if(op=="LOUT"){
    			if(pl<=pr)pl++;
    			else erro.push_back(i);
    		}else{
    			if(pl<=pr)pr--;
    			else erro.push_back(i);
    		}
    	}
    	for(int i=pl;i<=pr;i++)
    		cout<<p[i]<<" ";
    	cout<<endl;
    	for(int i:erro)
    		cout<<i<<" "<<"ERROR"<<endl;
    	return 0;
    }
    
    • 1
      @ 2022-1-2 22:20:18
      #include <bits/stdc++.h>
      using namespace std;
      int main()
      {
      	string a="LIN",b="RIN",c="LOUT",d="ROUT",m;
      	int n,x;
      	cin>>n;
      	int temp=n; 
      	deque <int> s;
      	queue <int> p;
      	while(n--)
      	{
      		cin>>m;
      		if(m==a)
      		{
      			cin>>x;
      			s.push_front(x);
      		}
      		else if(m==b)
      		{
      			cin>>x;
      			s.push_back(x);
      		}
      		else if(m==c)
      		{
      			if(!s.empty()) 
      			{
      			s.pop_front();
      		    }
      		    else p.push(temp-n+1);
      		}
      		else if(m==d)
      		{
      		   if(!s.empty()) 
      			{
      		     s.pop_back();
      		    }
      		    else p.push(temp-n);	
      		}
      	} 
      	while(!s.empty())
      	{
      		cout<<s.front();
      		s.pop_front();
      		s.empty()?cout:cout<<" "; 
      	}
      	cout<<endl;
      	while(!p.empty())
      	{
      		cout<<p.front();
      		p.pop();
      		cout<<" ERROR"<<endl; 
      	}
      	
      	return 0;
      }
      
      • 1
        @ 2022-1-2 11:19:47

        这里用到的是deque,并且需要一个数组来存储其错误的步骤

        #include<bits/stdc++.h>
        typedef long long ll;
        using namespace std;	
        string s;//使用string能够直接比较字符串,比用char方便很多;
        int a[100010];
        int main()
        {
        	int t,cnt=0;
        	cin>>t;
        	deque<int> q;
        	for(int i=1;i<=t;i++)
        	{
        		cin>>s;
        		if(s=="LIN")
        		{
        			int n;
        			cin>>n;
        			q.push_front(n);
        		}
        		if(s=="RIN")
        		{
        			int n;
        			cin>>n;
        			q.push_back(n);
        		}
        		if(s=="ROUT")
        		{
        			if(q.empty()) a[cnt++]=i;//储存错的步骤
        			else q.pop_back();
        		}
        		if(s=="LOUT")
        		{
        			if(q.empty()) a[cnt++]=i;
        			else q.pop_front();
        		}
        	}
        	while(!q.empty())
        	{
        		cout<<q.front()<<" ";
        		q.pop_front();
        	}cout<<endl;
        	for(int i=0;i<cnt;i++)
        	{
        		cout<<a[i]<<" "<<"ERROR"<<endl; 
        	}
        	return 0;
        }
        
        • 0
          @ 2022-3-29 14:58:04

          不知道有deque<int>,手写的倒序queue解决

          #include <bits/stdc++.h>
          using namespace std;
          
          queue<int> q1,q2;
          
          int main(){
              int n,total,num,error[10005] = {0};
              cin>>n;
              total = n;
              while(n--){
                  string ask;
                  cin>>ask;
                  if(ask == "LIN"){
                      cin>>num;
                      q2.push(num);
                  }
                  else if(ask == "RIN"){
                      cin>>num;
                      q1.push(num);
                  }
                  else if(ask == "LOUT"){
                      if(q2.empty() == false){
                          int chance = q2.back();
                          while(q2.front() != chance){
                              num = q2.front();
                              q2.pop();
                              q2.push(num);
                          }
                          q2.pop();
                          continue;
                      }
                      if(q1.empty() == false){
                          q1.pop();
                          continue;
                      }
                      error[total - n] = 1;
                  }
                  else if(ask == "ROUT"){
                      if(q1.empty() == false){
                          int chance = q1.back();
                          while(q1.front() != chance){
                              num = q1.front();
                              q1.pop();
                              q1.push(num);
                          }
                          q1.pop();
                          continue;
                      }
                      if(q2.empty() == false){
                          q2.pop();
                          continue;
                      }
                      error[total - n] = 1;
                  }
                  else{
                      error[total - n] = 1;
                  }
              }
          
              int size = q2.size();
              int left[size] = {0};
              for(int i = size - 1 ; i >= 0 ; i--){
                  left[i] = q2.front();
                  q2.pop();
              }
              for(int i = 0 ; i < size ; i++){
                  cout<<left[i]<<" ";
              }
              while(q1.empty() == false){
                  cout<<q1.front()<<" ";
                  q1.pop();
              }
              cout<<endl;
              for(int i = 1 ; i <= total ; i++){
                  if(error[i] == 1){
                      cout<<i<<" ERROR"<<endl;
                  }
              }
              return 0;
          }
          
          • 0
            @ 2022-3-27 20:33:56

            双向队列的基本操作

            #include<bits/stdc++.h>
            #include<string> 
            int t,x;
            using namespace std;
            int main(){
            	std::ios::sync_with_stdio(false);
            	deque <int> num;//操作双向队列 
            	queue <int> error;//记录error命令行数的队列
            	cin>>t;
            	for(int i=1;i<=t;i++){
            		string order;
            		cin>>order; 
            		if(order=="LIN"){//从头部入队一个元素 
            			cin>>x;
            			num.push_front(x);
            		}else if(order=="RIN"){//从尾部入队一个元素
            			cin>>x;
            			num.push_back(x);
            		}else if(order=="ROUT"){//从头部出队一个元素
            			if(!num.empty())
            				num.pop_back();
            			else
            				error.push(i);	
            		}else if(order=="LOUT"){//从尾部出队一个元素
            			if(!num.empty())
            				num.pop_front();
            			else
            				error.push(i);
            		}
            	}
            	while(!num.empty()){
            		cout<<num.front()<<" ";
            		num.pop_front();
            	}
            	cout<<endl;
            	while(!error.empty()){
            		cout<<error.front()<<" "<<"ERROR"<<endl;;
            		error.pop();
            	}
            	return 0;
            }
            
            • 0
              @ 2022-1-14 15:09:50
              #include<queue>
              #include<deque>
              #include<iostream>
              #include<string.h>
              using namespace std;
              
              int main()
              {
              	int n,a;
              	scanf("%d",&n);
              	char arr[10];
              	deque<int>que;
              	int num[10007];
              	for(int i = 1; i <= n; i++)
              	{
              		scanf("%s",arr);
              		if(strcmp(arr,"LIN") == 0)
              		{
              		scanf("%d",&a);
              		que.push_front(a);	
              		}
              		else if(strcmp(arr,"RIN") == 0)
              		{
              			scanf("%d",&a);
              			que.push_back(a);
              		}
              		else if(strcmp(arr,"ROUT") == 0)
              		{
              			if(!que.empty())
              			{
              				que.pop_back();
              			}
              			else
              			{
              				num[i]++;
              			}
              		}
              		else if(strcmp(arr,"LOUT") == 0)
              		{
              			if(!que.empty())
              			{
              				que.pop_front();
              			}
              			else
              			{
              				num[i]++;
              			}
              		}
              		
              	}
              	while(!que.empty())
              	{
              		printf("%d ",que.front());
              		que.pop_front();
              	}
              	puts("");
              	for(int i = 1;i <= n;i ++)
              	{
              		if(num[i] == 1)
              		{
              			printf("%d ERROR\n",i);
              		}
              	}
              	return 0;
              }
              
              
              • 0
                @ 2022-1-3 16:20:24

                一道入门的双向队列,没啥思路,就是模拟

                #include<stdio.h>
                #include<deque>
                #include<cstring>
                using namespace std;
                const int N=1e6+7;
                deque<int>s; 
                bool v[N];
                char a[N];
                int n;
                int main(){
                	scanf("%d",&n);
                	getchar();
                	for(int i=1;i<=n;i++){
                		scanf("%s",&a);
                		if(s.empty()){
                			if(a[1]=='O')v[i]=true;
                			else {
                				int h;
                				scanf("%d",&h);
                				if(a[0]=='L') s.push_front(h);
                				else s.push_back(h);//可以在每段最后面加一个输出队首队尾用于调试
                			}
                		}
                		else{
                			if(a[1]=='O'){
                				if(a[0]=='L') s.pop_front();
                				else s.pop_back();
                			}
                			else {
                				int h;
                				scanf("%d",&h);
                				if(a[0]=='L') s.push_front(h);
                				else s.push_back(h);
                			}
                		}
                	}
                	int t=0;
                	for(int i=1;i<=s.size()+t;i++){
                		printf("%d ",s.front());
                		s.pop_front();
                		t++; 
                	}
                	printf("\n");
                	for(int i=1;i<=n;i++)if(v[i])printf("%d ERROR\n",i);
                	return 0;
                }
                
                • 0
                  @ 2022-1-2 9:56:42

                  主要不会就上网查资料,多写几遍,就应该懂了

                  #include <cstdio>
                  #include <cstring>
                  #include <queue>
                  #include <deque>
                  #include <algorithm>
                  using namespace std;
                  const int N=1e6+7;
                  int main()
                  {
                      deque<int>q;//创建一个双向队列 
                      while(!q.empty())//将这个双向队列清空
                          q.pop_front();
                      int n,a,i,m[N]= {0};
                      scanf("%d",&n);
                      for(i=1; i<=n; i++)
                      {
                          char s[10];
                          scanf(" %s",s);
                          if(!strcmp(s,"LIN"))//将输入的字符串与“LIN”进行匹配,成功就进行下列操作
                          {
                              scanf("%d",&a);
                              q.push_front(a);//将输入的数从左边放入,也就是从头部放入
                          }
                          else if(!strcmp(s,"RIN"))//与上面类似
                          {
                              scanf("%d",&a);
                              q.push_back(a);//从右边放入,也就是从尾部放入
                          }
                          else if(!strcmp(s,"LOUT"))
                          {
                              if(!q.empty())
                                  q.pop_front();//从左边(头部)删除
                              else
                                  m[i]++;//记录位置
                          }
                          else if(!strcmp(s,"ROUT"))
                          {
                              if(q.empty())
                                  m[i]++;   
                              else
                                  q.pop_back();//从右边(尾部)删除
                          }
                      }
                      printf("%d",q.front()); //输出队列中的数
                      q.pop_front();//同时删除
                      while(!q.empty())//当队列不为空时继续输出然后删除直到队列中为空
                      {
                          printf(" %d",q.front());
                      q.pop_front();
                      }
                      printf("\n");
                      for(i=1; i<=n; i++)//输出不合法的操作
                          if(m[i])
                              printf("%d ERROR\n",i);
                      return 0;
                  }
                  
                  • 1

                  Information

                  ID
                  1125
                  Time
                  1000ms
                  Memory
                  128MiB
                  Difficulty
                  6
                  Tags
                  # Submissions
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                  Accepted
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