2022蓝桥杯大赛软件类国赛Java大学B组 左移右移 空间换时间+双指针

 
 
import java.util.Scanner;
 
public class Main {
   static Scanner sc=new Scanner(System.in);
   public static void main(String[] args) {
      
    int n=sc.nextInt();//数组长度
    int t=sc.nextInt();//操作次数
    int arr[]=new int[n];
    char arr1[] = new char[t];
    int  arr2[] = new int[t];
    int visited[]=new int[n+1];
    
    for(int i = 0 ;i<t ; i++) {
      arr1[i]=sc.next().charAt(0);
      arr2[i]=sc.nextInt();
    }
    
    //双指针
    int i=0;
    int j=n-1;
    
    for(int temp=t-1;temp>=0;temp--) {
      if(visited[arr2[temp]]==-1)continue;
      if(arr1[temp]=='R') {
        arr[j]=arr2[temp];
        j--;
        visited[arr2[temp]]=-1;
      }
      if(arr1[temp]=='L') {
        arr[i]=arr2[temp];
        i++;
        visited[arr2[temp]]=-1;
      }
    }
    int p=1;
    for(int b=0;b<n;b++) {
      if(arr[b]==0) {
        while(visited[p]==-1) {
          p++;
        }
        visited[p]=-1;
        System.out.print(p+" ");
      }
      else System.out.print(arr[b]+" ");
    }
   } 
}