#include <stdio.h>
#include <stdlib.h>

typedef struct
{
	int id;
	int time;	
} PE;

int cmp(const void *a, const void *b)
{
	PE *c = (PE *)a;
	PE *d = (PE *)b;
	
	if(c->time == d->time) return c->id - d->id;
	else return d->time - c->time;	
}

int main()
{
	PE peo[10005];
	int i,in;
	int m,n;
	
	while(scanf("%d%d",&n,&m)!=-1)
	{
		if(m==0 && n==0) break;
		for(i=0;i<10005;i++)
		{
			peo[i].id=i;
			peo[i].time=0;	
		}
		for(i=0;i<n*m;i++)
		{
			scanf("%d",&in);
			peo[in].time++;	
		}
			
		qsort(peo,10005,sizeof(peo[0]),cmp);
		
		for(i=1;peo[i].time==peo[1].time;i++)
		{
			printf("%d ",peo[i].id);	
		}
		printf("\n");
	}
	
	
	return 0;	
}