C > Beginners Lab Assignments

Square root of a number without using Built-In Function

Square root of a number without using Built-In Function

#include<stdio.h>
#include<conio.h>

void main()
{
 double n,g1,g2;
 int flag=0;
 clrscr();
 printf("Enter the no.: ");
 scanf("%lf",&n);
 if(n<0)
 {
                n=-n;
                flag=1;
 }
 else if(n==0)
 {
                printf("
The root of %6.4lf is",n);
                textcolor(GREEN);
                cprintf(" %6.4lf",g2);
                getch();
                exit(0);
 }
 g2=n/2;
 do
 {
                g1=g2;
                g2=(g1+n/g1)/2;
 }
 while((g1-g2)!=0);
 if(flag==1)
 {
                printf("
The root of %6.4lf is",-n);
                textcolor(GREEN);
                cprintf(" +/- %6.4lf i",g2);
 }
 else
 {
                printf("
The root of %6.4lf is",n);
                textcolor(GREEN);
                cprintf(" +/- %6.4lf",g2);
 }
 getch();
}