#include<stdio.h>
int main(){
    int n,x,i,j,found = 0;
    int arr[100];
    scanf("%d",&n);
    for(i=0;i<n;i++)
    scanf("%d%d",&x,&arr[i]);
    for(i=0;i<n;i++){
        if(arr[i]==x){
            found=1;
            for(j=1;j<n-1;j++)
            arr[j]=arr[j+1];
            n--;
            break;
        }
    }
    if(found){
        for(i=0;i<n;i++){
            printf("%d",arr[i]);
        }
        else
        {
            printf("Marble not found");
        }
    }
}