Formatted question description: https://leetcode.ca/all/1979.html

# 1979. Find Greatest Common Divisor of Array

## Level

Easy

## Description

Given an integer array `nums`

, return *the greatest common divisor of the smallest number and largest number in nums*.

The **greatest common divisor** of two numbers is the largest positive integer that evenly divides both numbers.

**Example 1:**

**Input:** nums = [2,5,6,9,10]

**Output:** 2

**Explanation:**

The smallest number in nums is 2.

The largest number in nums is 10.

The greatest common divisor of 2 and 10 is 2.

**Example 2:**

**Input:** nums = [7,5,6,8,3]

**Output:** 1

**Explanation:**

The smallest number in nums is 3.

The largest number in nums is 8.

The greatest common divisor of 3 and 8 is 1.

**Example 3:**

**Input:** nums = [3,3]

**Output:** 3

**Explanation:**

The smallest number in nums is 3.

The largest number in nums is 3.

The greatest common divisor of 3 and 3 is 3.

**Constraints:**

`2 <= nums.length <= 1000`

`1 <= nums[i] <= 1000`

## Solution

Get the smallest number and the largest number in `nums`

and calculate the greatest common divisor.

```
class Solution {
public int findGCD(int[] nums) {
Arrays.sort(nums);
int minNum = nums[0], maxNum = nums[nums.length - 1];
return gcd(minNum, maxNum);
}
public int gcd(int a, int b) {
if (a > b) {
int temp = a;
a = b;
b = temp;
}
if (b % a == 0)
return a;
return gcd(a, b % a);
}
}
```