Aplication accepts string *800# menu list and allows user navigate through menu by choosing numbers corresponding to menu item.

menu

*800#

option

1-balances;

2-buy ;

3-buy airtime;

4-buy SMS;

5-quit;

action

Go to next menu

menu

1balance

option

1-talk balance;

2-data balance;

3-quit;

action

Print message :you have requested balance for :(option chosen)

menu

2buy data

option

1-500mb;

2-1gb;

3-quit;

action

Print message :you have purchased data bundle for:(option chosen)

menu

3buy airtime

option

1-R20.00;

2-R40.00;

3-quit;

action

print message :you have purchased airtime for :(chosen option)

menu

quit

action

Print message :thank you, goodbye

Use of separation concerns, get various decisions such as switch cases, if statements