#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct tree{
    int data;
    char name[20];
    struct tree *left;
    struct tree *right;
}nd;
nd *root=NULL;
nd *create(int val,char *a){
    nd *newnode=(nd*)malloc(sizeof(nd));
    newnode->data=val;
    strcpy(newnode->name,a);
    newnode->left=NULL;
    newnode->right=NULL;
    return newnode;
}
nd *insertBTlvlor(int a[],int n){
    if(n==0||a[0]==0){
        return NULL;
    }
    nd *q[100];
    int front=0,rear=0;
    nd *root=create(a[0]);
    q[rear++]=root;
    int i=1;
    while(i<n &&front<rear){
        nd *curr=q[front++];
        if(i<n&&a[i]!=0){
            curr->left=create(a[i]);
            q[rear++]=curr->left;
        }
        i++;
        if(i<n&&a[i]!=0){
            curr->right=create(a[i]);
            q[rear++]=curr->right;
        }
        i++;
    }
    return root;
}
void lvlordtrav(nd *root){
    if(root==NULL){
        return;
    }    
    nd *q[50];
    int front=0,rear=0;
    queue[rear++]=root;
    while(front<rear){
        nd *temp=q[front++];
        printf("%d %s\n",temp->data,temp->name);
        if(temp->left){
            q[rear++]=temp->left;
        }
        if(temp->right){
            q[rear++]=temp->right;
        }
    }
}
int main(){
    int n;
    scanf("%d",&n);
    if(n<0){
        printf("Invalid input");
    }
    int t;char name[20];
    nd *root=NULL;
    for(int i=0;i<n;i++){
        scanf("%49[^,]%d",,name &t);
        if(t<0){
            printf("Invalid input");
            return 0;
        }
    }
    root=insertBTlvlor(root,t,name);
    lvlordtrav(root);
    return 0;
}