## Discussion Forum

Que. | A function f defined on stacks of integers satisfies the following properties. f(∅) = 0 and f (push (S, i)) = max (f(S), 0) + i for all stacks S and integers i.
If a stack S contains the integers 2, -3, 2, -1, 2 in order from bottom to top, what is f(S)? |

a. | 6 |

b. | 4 |

c. | 3 |

d. | 2 |

Answer:3 |