C++ Tutorial/Development/typedef

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Use typedef keyword to define new variable type

#include <iostream>
 
 typedef unsigned short int USHORT;       
 
 int main()
 {
    USHORT Width = 5;
    USHORT Length;
    Length = 10;
    USHORT Area = Width * Length;
    std::cout << "Width: " << Width << "\n";
    std::cout << "Length: " << Length << std::endl;
    std::cout << "Area: " << Area << std::endl;
    return 0;
 }
Width: 5
Length: 10
Area: 50

Use typedef to create new data type and use it as function return type

#include <cmath>
#include <iostream>
using namespace std;
typedef double NewType;
NewType f(double number);
NewType f2(double number);
NewType f3(double number);
int main()
{
       int menu;
       double num;
       NewType response;
    response = f(num);
    cout << "The answer is " << response;
    
    response = f2(num);
    cout << "The answer is " << response;
    
    response = f3(num);
    cout << "The answer is " << response;
       
       return 0;
}
NewType f(double number)
{
   return sqrt(number);
}
NewType f2(double number)
{
   return pow(number,.3333);
}
NewType f3(double number)
{
   return pow (number,.25);
}
The answer is 2.29873e-154The answer is 3.8421e-103The answer is 1.51616e-077"