## GCD of two numbers in Python

In the program, we will learn to find the GCD of two numbers that is Greatest Common Divisor.

**The highest common factor (HCF) or Greatest Common Divisor (GCD) of two given numbers is the largest or greatest positive integer that divides the two number perfectly.**

For example, here, we have two numbers 12 and 14

Output: GCD is 2

**Algorithm:**

- Define a function named gcd(a,b)
- Initialize small =0 and gd =0
- If condition is used to check if a is greater than b.
- if true small==b, else small==a.
- using for loop with range(1, small+1), check if((a % i == 0) and (b % i == 0))
- if true gd=I and gd value is returned in variable t
- Take a and b as input from the user.
- The function gcd(a,b) is called with a and b as parameters passed in the function.
- Print the value in the variable t.
- Exit

**Code:**

```
def gcd(a,b):
small=0
gd=0
if a>b:
small==b
else:
small==a
for i in range(1, small+1):
if((a % i == 0) and (b % i == 0)):
gd=i
return gd
a=int(input("Enter the first number: "))
b=int(input("Enter second number: "))
t=gcd(a,b)
print("GCD is:",t)
```

**Output:**

```
Enter the first number: 60
Enter second number: 48
GCD is: 12
```

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