#include<stdio.h>
#include<math.h>
int n,i,j,k,m;
char s[17];
int a[30001][26],used[30001],n[17];
int main()
{freopen("restante.in","r",stdin);
 freopen("restante.out","w",stdout);
 scanf("%d",&n);
 for(i=1;i<=n;i++){
  scanf(" %s ",s);
  j=0;m=0;
  while(s[j]){a[i][s[j]-'a']++;j++;}}
 m=0;
 for(j=0;j<26;j++){
  for(i=1;i<=n;i++)
   if(!used[i]) n[a[i][j]]++;
  for(k=0;k<=16;k++)
   if(n[k]==1)
    for(i=1;i<=n;i++)
     if(!used[i]&&a[i][j]==k) {m++;used[i]=1;}
  }
 printf("%d",m);
 fclose(stdout);
 return 0;}