#include
int main()
{
struct Date
{
int month;
int day;
}Date[100];
int i=0,j,k,t1,t2,temp;
while(scanf("%d %d",&Date[i].month,&Date[i].day)!=EOF)
{
if(Date[i].month==0&&Date[i].day==0)break;
else i++;
}
for(j=0;j {
for(k=j+1;k {
if(Date[j].month>Date[k].month)
{
t1=Date[j].month;
t2=Date[j].day;
Date[j].month=Date[k].month;
Date[j].day=Date[k].day;
Date[k].month=t1;
Date[k].day=t2;
}
else if(Date[j].month==Date[k].month)
{
if(Date[j].day>Date[k].day)
{
temp=Date[j].day;
Date[j].day=Date[k].day;
Date[k].day=temp;
}
}
}
}
for(j=0;j {
printf("%d %dn",Date[j].month,Date[j].day);
}
}



