C++ Part 25

Functions

• Breaks code down into manageable chunks to write (and divide across development team)
• Easier to debug – only one idea behind each module
• Easier to maintain – buggy modules may be replaced without worrying about ramifications on other modules
• Outsiders only need to know a module’s interface, not the details of its implementation.
• Avoids duplication of code ⇒ more compact, and also easier to modify if code has bug  

• Predefined functions: e.g., String.length(): String → Int  
• Programmer-Defined functions: used similarly to predefined functions  
  
  This predefined functions need using namespace std;
  

Source : Absolute C++

C++ Part 19

The switch statement is the only other kind of C++ statement that implements
multi way branches.

switch Statement switch (Controlling_Expression) { case Constant_1: Statement_Sequence_1 break; case Constant_2: Statement_Sequence_2 break; . . . case Constant_n: Statement_Sequence_n break; default: Default_Statement_Sequence }

Example :

#include <iostream> using namespace std; int main() {    int vehicleClass; double toll; cout << "Enter vehicle class '1-3': "; cin >> vehicleClass; switch (vehicleClass) { case 1: cout << "Passenger car."; toll = 0.50; break; case 2: cout << "Bus."; toll = 1.50; break; case 3: cout << "Truck."; toll = 2.00; break; default: cout << "Unknown vehicle class!"; } /* If you forget this break, then passenger cars will pay $1.50. You need not place a break statement in each case. If you omit a break, that case continues until a break (or the end of the switch statement) is reached. */    return 0; }