Assignment 4 · Interval Math Library — Advanced Functions

Module 8 (L15–L16) · 40 marks · due end of Week 9 Outcomes: CLO-5 (PF-8.x)

Build a tiny library for closed intervals [lo, hi] on integers, exercising overloading, default arguments, recursion, and passing modes.

Required API (signatures fixed)

bool  isValid(int lo, int hi);                     // lo <= hi
bool  contains(int lo, int hi, int v);             // lo <= v <= hi
bool  overlap(int lo1, int hi1, int lo2, int hi2); // intervals share >= 1 point
int   clamp(int v, int lo = 0, int hi = 100);      // force v into [lo,hi] (default [0,100])
int   sumRange(int lo, int hi);                    // recursive sum lo..hi inclusive (isValid precondition)
void  swapInts(int& a, int& b);                    // exchange values
int   length2d(int w, int h, int depth = 1);       // overloading demo: volume of box
int   length2d(int w, int h);                      // 2-D overload: w*h

main must demonstrate every function with at least one call each, printing labeled results, including one default-argument call and one explicit-argument call of clamp.

Sample output shape (labels must match)

isValid(3,1)     -> no
contains(0,10,5) -> yes
overlap(0,5,5,9) -> yes
clamp(150)       -> 100
clamp(150,0,50)  -> 50
sumRange(1,5)    -> 15
swap 2,9         -> 9,2
length2d(3,4)    -> 12
length2d(3,4,2)  -> 24

Constraints

• sumRange must be recursive with a stated base case (no loops inside).
• No global variables. All state travels through parameters/returns.
• Passing modes: value for inputs, int& only where mutation is the contract (swap).

Deliverables

intervals.cpp (contract, zero warnings) · test_table.md — touching intervals (overlap yes), disjoint (no), degenerate [5,5] contains/overlap, clamp on all three branches, sumRange with lo == hi, swap of same variable aliased via two names (document the result) · postmortem.md (10 marks).

Notes

• Touching intervals share exactly one point — they overlap.
• sumRange with lo > hi violates its precondition; assert-free handling is to document the precondition, not to "fix" inputs silently.