//x^2-2x-3, x^2-2x+1, x^2+2x+3 -> Try coefficients for a,b,c respectively for these equations

#include<stdio.h> // Import Standart Input-Output Library
#include<math.h>  // Import Math Library
main() // This function (main) is where main code starts and ends
{
float disc, b, a, c, t0, t1, sol0, sol1; // defining float variables, notice also the semicolon end of expression
printf("a: ");   
scanf("%f",&a); // Waiting input from user for each coefficient  
printf("b: ");
scanf("%f",&b); // Waiting input from user for each coefficient  
printf("c: ");
scanf("%f",&c); // Waiting input from user for each coefficient  
disc = (b * b - 4 * a * c); //Calculating discriminant
int num_sol;
//-------------------------------------------------------------------
// 'if'-'else if'-'else' structure in C, notice the curly braces which determines scope of a code piece belonging to 'if', 'else if' or 'else'.  
// Same rule applies to 'if' or 'If'-'else'. Also same thing applies to functions, while and for loops.
if (disc < 0)  
{
    num_sol = 0; // Zero solution if discriminant is negative
	
}
else if (disc>0)
{
	num_sol=2; // Two solutions if discriminant is bigger than zero
	sol0=(-b-(sqrt(disc)))/(2*a); // Calculating first solution
        sol1=(-b+(sqrt(disc)))/(2*a); // Calculating second solution
	printf("Solutions: %f, %f ", sol0,sol1); // Printing the solutions
}
else
{
num_sol = 1; // Two overlapped solution into a one value
sol0 = (-b)/(2*a); // Calculating the only solution
printf("Solution: %f ",sol0); //Printing the solution

}
//---------------------------------------------------------------------
printf("Solution found: %d", num_sol); // Printing the solution number
return 0;
}

//**********************************************************************************************************************************************************

// Implementing a recursive greatest common divisor algorithm
#include<stdio.h>

int gcd(int a, int b) // Defining a function, notice the curly braces and parameter definitions (first integer parameter, second integer parameter)
{ // If you want that 'if' or 'else if' or 'else' include just one code line below them, then don't put the curly braces,the same thing applies to loops.  
  if (b == 0)
    return a; 
  else
    return gcd(b, a % b); //Calling itself, 'a%b' means a mod b
}
main()
{
int x,y;
printf("Enter 1st number: ");
scanf("%d",&x);
printf("Enter 2nd number: ");
scanf("%d",&y);
printf("GCD of (%d, %d): %d\n ",x,y, gcd(x, y));
return 0;
}

//**********************************************************************************************************************************************************

// Implementing a program finding the maximum value of given numbers
#include<stdio.h>
main()
{
int value_list[5]={3,2,60,5,7}; // Creating an array with five elements and assigning elements to it
int foundmax=value_list[0]; //Defining an integer variable and assigning first element of the array to it 
int i; 
for(i=1;i<5;i++) // Defining a for loop, notice the curly braces and expressions (first assignment;condition;increment)
{
	if (foundmax<value_list[i]) // Comparing 'foundmax' variable to i.element of 'value_list' array
	 foundmax=value_list[i];  //Assigning  i.element of 'value_list' array to 'foundmax'
}
printf("Greatest element of list: %d\n",foundmax);
return 0;
}