#include<stdio.h>
#include<string.h>
int n,i,j,k,m;
char s[17];
int a[36001][26],used[36001],nr[26][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);
  m=strlen(s);
  for(j=0;j<m;j++) a[i][s[j]-'a']++;}
 m=0;
 for(j=0;j<='z'-'a';j++){

  for(i=1;i<=n;i++)
   nr[j][a[i][j]]++;

  for(k=0;k<=16;k++)
   if(nr[j][k]==1)
    for(i=1;i<=n;i++)
     if(!used[i]&& a[i][j]==k) {m++;used[i]=1;break;}
  }
 printf("%d",m);
 fclose(stdout);
 return 0;}