import java.util.*;
class main{
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        int arr[]=new int[n];
        int arr1[]=new int[n];
        for(int i=0;i<n;i++){
             if(!sc.hasNextInt()){
                System.out.print("Invalid input");
                return;
            }
            arr[i]=sc.nextInt();
           arr1[i]=sc.nextInt();
        }
        int k=sc.nextInt();
        if(k==1){
        for(int i=0;i<n;i++){
            for(int j=i+1;j<n;j++){
                if(arr[i]>arr[j]){
                    int temp=arr[i];
                    arr[i]=arr[j];
                    arr[j]=temp;
                }
            }
            System.out.print(arr[i]+" ");
        }
        }else if(arr[i]==arr1[i]){
             System.out.print("-1");
             return;
        }
        else if(k==2){
        for(int i=0;i<n;i++){
            for(int j=i+1;j<n;j++){
                if(arr[i]<arr[j]){
                    int temp=arr[i];
                    arr[i]=arr[j];
                    arr[j]=temp;
                }
            }
            System.out.print(arr[i]+" ");
        }
        }
    }
}