#include "stdio.h"int main(void) {
       int num;    int length;    char str_out[100][51];    int index;    int index1;    int result[100];    int a=0;    int b=0;    int min=0;    int num2=0;    int temp;    int min_index;    #ifndef ONLINE_JUDGE    freopen("in.txt","r",stdin);    #else    #endif    scanf("%d%d",&length,&num);    num2=num;    temp=num2;    while(num>0){
           scanf("%s", str_out[a]);        if(num2 == 1){
              printf("%sn",str_out[a]);           return 0;        }        result[a] = 0;        for(index=0;index
    
      str_out[a][index1])result[a]++;               }            }        }    num--;    a++;    }    while(num2>0){
       if(result[b]==5000)    {
           b++;        continue;    }    min = result[b];    min_index = b;    for(index=0;index
     
       result[index+1]){
              min = result[index+1];           min_index =index+1;        }    }    result[min_index] = 5000;    num2--;    printf("%sn",str_out[min_index]);    min_index = 0;}    #ifndef ONLINE_JUDGE    fclose(stdin);    #else    #endif    return 0;