Naive methods for calculating gcd
 Using recursion :
 Using
# Python code to demonstrate naive
# method for calculating gcd (Loops)
def
computeGCD (x, y):
if
x" y:
small
=
y
else
:
small
=
x
for
i
in
range
(
1
, small
+
1
):
if
((x
%
i
=
=
0
)
and
(y
%
i
=
=
0
)):
gcd
=
i
return
gcd
a
=
60
b
=
48
# prints 12
print
(
" The gcd of 60 and 48 is: "
, end
=
" ")
print
(computeGCD (
60
,
48
))
Output:
The gcd of 60 and 48 is: 12
 Using the
# Python code to demonstrate naive
# method for calculating gcd (euclidean algo)
def
computeGCD (x, y):
while
(y):
x , y
=
y, x
%
y
return
x
a
=
60
b
=
48
# prints 12
print
(
"The gcd of 60 and 48 is:"
, end
=
" ")
print
(computeGCD (
60
,
48
))
Output:
The gcd of 60 and 48 is: 12

Output:
The gcd of 60 and 48 is: 12
Using the Python math.gcd () function
Using gcd () can evaluate the same gcd in just one line.
math.gcd (x, y) Parameters: x: Nonnegative integer whose gcd has to be computed. y: Nonnegative integer whose gcd has to be computed. Return Value: This method will return an absolute / positive integer value after calculating the GCD of given parameters x and y. Exceptions: When Both x and y are 0, function returns 0, If any number is a character, Type error is raised.
# Python code for demonstrating gcd ()
# method for calculating gcd
import
math
# prints 12
print
(
"The gcd of 60 and 48 is:"
, end
=
"")
print
(math.gcd (
60
,
48
))
Output:
The gcd of 60 and 48 is: 12
Common exceptions
Some common exceptions in this function:
 Both numbers are 0, gcd is 0
 If only one number is not a number, a type error occurs.

Output:
The gcd of 0 and 0 is: 0 The gcd of a and 13 is:
Runtime error:
Traceback (most recent call last) : File "/home/94493cdfb3c8509146254862d12bcc97.py", line 12, in print (math.gcd (’a’, 13)) TypeError:’ str’ object cannot be interpreted as an integer
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