#include <iostream>
#include <cstring>
using namespace std;

int main()
{
    char a[31],b[31],aux[31];
    int ok=1;
    cin>>a>>b;
    for(int i=0;i<strlen(a);i++)
        if(strchr(b,a[i])==0) ok=0;
        else
        {
            strcpy(aux,strchr(b,a[i])+1);
            strcpy(b,aux);
        }
    if(ok) cout<<"DA";
    else cout<<"NU";
    return 0;
}