import java.util.Arrays;

public class Cashier {

    private int cash = 0;
    private String text[] = {"x £50 note", "x £20 note", "x £10 note", "x £5 note","x £2 coin","x £1 coin"}; //can be adjusted if new types of bills/coins are put into circulation
    private int notes[] = {50, 20, 10, 5, 2, 1};
    private int totals[] = {0,0,0,0,0,0};

    public Cashier() {}

    public String produceChange(int cash) {
        this.cash = cash;
      
      for(int i=0;i<notes.length;i++){
        while(cash>(notes[i]-1)){
          cash -= notes[i];
          totals[i]++;
        }
      }
        return this.toString();
    }

    public String toString() {
      int totalNotes =  Arrays.stream(Arrays.copyOfRange(totals, 0, 4)).sum();  //can be adjusted if new types of bills/coins are put into circulation
      int totalCoins = Arrays.stream(Arrays.copyOfRange(totals, 4, 6)).sum();
      String out ="For £" + cash + " - change was "+ totalNotes  + (totalNotes == 1 ? " note and " : " notes and ") + totalCoins + (totalCoins == 1 ? " coin: " : " coins: ");
      boolean commaFlag = false;
      for(int i=0;i<notes.length;i++){
         if(totals[i] != 0){
           out+=(commaFlag?", ":"")+totals[i]+text[i]; 
           //uncomment next line to propperly add 's' at end of bill/coin counts, example: "3x £50 note" --> "3x £50 notes"
           //totals[i]>1?out+="s":"";
           commaFlag = true;
         }
      }
      
        Arrays.fill(totals, 0);
        return out;
    }
}