/*Goal: write a function called printMessage()
**that prints: Functions!
*/

#include<iostream>

void printMessage();

int main()
{

    printMessage();
    return 0;
}

void printMessage()
{
    std::cout<<"Functions";
}

/*GOAL: Practice writing functions

/*Write a function called printProduct that prints the results of the multiplication 
**of two integers. 
*/

#include <iostream>
int printProduct(int m1, int m2, int product);

int main()
{
    int m1 = 4;
    int m2 = 5;
    int product;

    product = m1 * m2;
    
    printProduct(m1, m2, product);
    return 0;
}

int printProduct(int m1, int m2, int product){
    std::cout << m1 << " * " << m2 << " = " << product << "\n";
}

/*Put your functions here. 
**The grader will use this file to check your work. 
*/

#include<iostream>

void printEquation(int m1, int m2, int sum, char operation) 
{
    std::cout<<m1<<" "<<operation<<" "<<m2<<" = " <<sum;
}

int sum(int m1, int m2)
{
    return m1 + m2;
}

#include "main.hpp"

int main()
{
    int m1 = 33; 
    int m2 = 66;
    printEquation(m1, m2,sum(m1, m2),'+');
    return 0;
}

/*The program is changed to return 
**the modified variable 'a'
**
**P.S. This is a totally silly program. Why write a function, 
**with all the function overhead, to increment a variable?
**Silly!
*/

#include<iostream>

int increment(int input);
int main()
{
    int a = 34;
    std::cout<<"Before the function call a = "<<a<<"\n";
    a = increment(a);
    std::cout<<"After the function call a = "<<a<<"\n";
    return 0;
}
int increment(int input)
{
    input++;
    std::cout<<"In the function call a = "<<input<<"\n";
    return input;
}

/*Goal: Learn to pass variables by reference. 
**Once we learn this, we can modify variables in functions,
**and the change will be available outside the scope of the 
**modification.
*/

#include<iostream>

void increment(int &input); //Note the addition of '&'

int main()
{
    int a = 34;
    std::cout<<"Before the function call a = "<<a<<"\n";
    increment(a);
    std::cout<<"After the function call a = "<<a<<"\n";
    return 0;
}
void increment(int &input)//Note the addition of '&'
{
    input++; //**Note the LACK OF THE addition of '&'**
    std::cout<<"In the function call a = "<<input<<"\n";
}

#include "main.hpp"

int main()
{
    char operation = '/';
    float input1 = 9.8;
    float input2 = 2.3;
    float result;

    calculate(input1, input2, operation, result);
    printEquation(input1, input2, operation, result);
    return 0;
}

/*The header file for main.cpp*/

#include<iostream>

void calculate(float in1, float in2, char op, float &ans);
void printEquation(float input1,float input2, char operation, float result);

void calculate(float in1, float in2, char op, float &ans)
{
    switch(op)
    {
        case '+': ans = in1 + in2;
                  break;
        case '-': ans = in1 - in2;
                  break;   
        case '*': ans = in1 * in2;
                  break;
        case '/': ans = in1 / in2;
                  break;
        default:  std::cout<<"Illegal operation\n";
    }
}
void printEquation(float input1,float input2, char operation, float result)
{
    std::cout<<input1<<" "<<operation<<" "<<input2<<" = "<<result<<"\n";
}

void functionName(variableType *arrayName)
void functionName(variableType arrayName[length of array])
void functionName(variableType arrayName[])

/*Goal: Learn to pass arrays to functions*/

#include<iostream>
#include<iomanip>

//Pass the array as a pointer
void arrayAsPointer(int *array, int size);
//Pass the array as a sized array
void arraySized(int array[3], int size);
//Pass the array as an unsized array
void arrayUnSized(int array[], int size);

int main()
{
    const int size = 3;
    int array[size] = {33,66,99};
    //We are passing a pointer or reference to the array
    //so we will not know the size of the array
    //We have to pass the size to the function as well
    arrayAsPointer(array, size);
    arraySized(array, size);
    arrayUnSized(array, size);
    return 0;
}

void arrayAsPointer(int *array, int size)
{
    std::cout<<std::setw(5);
    for(int i=0; i<size; i++) 
        std::cout<<array[i]<<" ";
    std::cout<<"\n";
}

void arraySized(int array[3], int size)
{
    std::cout<<std::setw(5);
    for(int i=0; i<size; i++)
        std::cout<<array[i]<<" ";
    std::cout<<"\n";  
}

void arrayUnSized(int array[], int size)
{
    std::cout<<std::setw(5);
    for(int i=0; i<size; i++)
        std::cout<<array[i]<<" ";
    std::cout<<"\n";  
}

/*Goal: create a function that searches an array for 
**a given value. 
*/

#include<iostream>

int search(int array[], int size, int searchKey);

int main()
{
    const int size = 4;
    int array[] = {345,75896,2,543};
    int searchKey = 543;
    std::cout<<"Found at: "<<search(array, size, searchKey);
    return 0;
}

int search(int array[], int size, int searchKey)
{
    int found = -1;
    for(int i=0; i<size;i++)
    {
        if(array[i] == searchKey)
        {
            found=i;
        }
    }
    return found;
}

int doubleInput(const int input)

int doubleInput(const int input)
{
    int h = input *2;
    return h;
}