CalebCurry

#ifndef HEADER_FILE //include guards prevent multiple includsion
#define HEADER_FILE //if not yet defined, define it
//optional but recommended

int square (int input);
int cube(int input);
int power(int input, int exponent);
int recursivePower(int input, int exponent);
void changeVal(int *a);
int oldestValue( int *ages, int size);

CalebCurry

#include "5.2-libraries.h"

int square (int input)
{
    return input * input * input;
}
int cube(int input)
{
    return input * input * input;
}

CalebCurry

/*
gcc -c 5.2-libraries.c
cc -c 5.2-libraries-main.c
gcc 5.2-libraries.o 5.2-libraries-main.o
./a.out

You can also get a custom name like this:
gcc -o main 5.2-libraries.o 5.2-libraries-main.o

//research makefile to make life easier

CalebCurry

#include <stdio.h>

int square (int input)
{
    return input * input;
}
int cube(int input)
{
    return input * input * input;
}

CalebCurry

#include <stdio.h>
#include <string.h>

int main()
{
    //strings are just character arrays
    //the string ends with \0 (null character)
    //not always the last possible index in the string.

    char name[20];

CalebCurry

#include <stdio.h>

int main()
{
    //arrays are pretty simple.
    //It's a collection of items all of same data type

    int ages[] = {1, 3, 4, 54, 34, 2};
    int size = 6;

CalebCurry

//loops. 3 main kinds

#include <stdio.h>

int main()
{ 
    //Each loop has three pieces and it happens at distinct times
    //initialization (once at beginning)
    //comparison (before each iteration)
    //update (at the end of each iteration)

CalebCurry

/*

Everything inside of if is ultimately evaluated to true or false

*/

#include <stdio.h>
#include <stdbool.h>

int main()

CalebCurry

#include <stdio.h>

int main()
{
    /*
    //reference - https://www.tutorialspoint.com/cprogramming/c_operators.htm

    //so far we've worked with some basic operators
    /////////////   Plus and Minus   ///////////// (unary)
        +

CalebCurry

#include <stdio.h>
#include <stdbool.h>

int main()
{
    int a = 10; //integer
    double b = 10.0; //double
    float c = 10.0; //float (similar to double but less precise)
    char d = 'a'; //string
    char e[] = "The easiest way to define a string";