#include<cstdio>#include<algorithm>#include<map>using namespace std;int main(){    map<int ,int>mp;    int n;    while(~scanf("%d",&n)&&n)    {        int id,fg;        mp[1000000000]=1;        for(int i=0; i<n; i++)        {           scanf("%d %d",&id,&fg);            mp[fg]=id;            map<int ,int>::iterator it=mp.find(fg),it1;            if(it==mp.begin())                printf("%d %d\n",id,(++it)->second);            else            {                it1=it;                if(abs((--it)->first-fg)<=abs((++it1)->first-fg))                    printf("%d %d\n",id,(it)->second);                else                  printf("%d %d\n",id,(it1)->second);            }        }        mp.clear();    }    return 0;}