Răspuns:
#include <iostream>
#include <fstream>
using namespace std;
ifstream f("date.in");
int n,a[101];
int main(){
f>>n;
for(int i=1;i<=n;i++){
cin>>a[i];
int f[101]={0};
while(a[i])
f[a[i]%10]++,a[i]/=10;
}
for(int i=0;i<=9;i++)
if(f[i]==1)
cout<<i<<" ";
return 0;
}