Greatest common divisor of four

Write a function that computes the greatest common divisor of four natural numbers $a$ , $b$ , $c$ and $d$ using the fast version of the Euclidean algorithm.

Interface

C++,C	`int gcd4(int a, int b, int c, int d);`
Java	`public static int gcd4(int a, int b, int c, int d);`
Python	`gcd4(a, b, c, d) # returns int`
	`gcd4(a: int, b: int, c: int, d: int) -> int`

Precondition

The four numbers are strictly greater than zero.

Observation

You only need to submit the required procedure; your main program will be ignored.

Problem information

Author: Unknown
Translator: Salvador Roura

Generation: 2026-09-01T07:39:53.297Z