Square Root Program In C

The process of finding square root of a number can be divided into two steps. One step is to find integer part and second one is for fraction part.

Algorithm

We derive an algorithm for finding square root here −

START
   Step 1 → Define value n to find square root of
   Step 2 → Define variable i and set it to 1 (For integer part)
   Step 3 → Define variable p and set it to 0.00001 (For fraction part)
   Step 4 → While i*i is less than n, increment i
   Step 5 → Step 4 should produce the integer part so far
   Step 6 → While i*i is less than n, add p to i
   Step 7 → Now i has the square root value of n
STOP

Pseudocode

The pseudocode of this algorithm can be derived as follows −

procedure square_root( n )
   
   SET precision TO 0.00001
   FOR i = 1 TO i*i < n DO
      i = i + 1
   END FOR

   FOR i = i - 1 TO i*i < n DO
      i = i + precision
   END FOR
   DISPLAY i AS square root

end procedure

Implementation

Implementation of this algorithm is given below −

#include <stdio.h>

double squareRoot(double n) {
   double i, precision = 0.00001;

   for(i = 1; i*i <=n; ++i);           //Integer part

   for(--i; i*i < n; i += precision);  //Fractional part

   return i;
}

int main() {
   int n = 24;

   printf("Square root of %d = %lf", n, squareRoot(n));

   return 0;
}

Output

Output of the program should be −

Square root of 24 = 4.898980