Given an array, write a program to find the maximum GCD among all the subarray of the size >= 2 of the given array.

**Examples:**

Input list:[2, 3, 4, 4, 4]Output:4Input list:[3, 7, 2, 9, 18, 5, 1, 13 ]Output:9

### Approach:

- Import the math module for python
- Introduce a variable(say, V1) to store the gcd of each element of the list while looping through the list.
- Iterate through the elements of the array or list using a loop.
- At each iteration call the
**math.gcd() function.** - Store the outcome of the math.gcd() function to another variable (say, V2) at each iteration.
- Now compare V1 and V2. If V2 is greater than V1, set V1 equal to V2 else pass.
- Let the loop run through and print out the final value of V1.

Below you can find the implementation of the above-mentioned approach:**Examples 1:**

## Python3

`import` `math` ` ` `# input list` `List` `=` `[` `2` `, ` `3` `, ` `4` `, ` `4` `, ` `4` `]` ` ` `max1 ` `=` `0` `for` `i ` `in` `range` `(` `len` `(` `List` `)` `-` `1` `):` ` ` ` ` `# use math.gcd() function` ` ` `gcd1 ` `=` `math.gcd(` `List` `[i], ` `List` `[i ` `+` `1` `])` ` ` `if` `(gcd1>max1):` ` ` `max1 ` `=` `gcd1` ` ` `# print max1` `# as the result` `print` `(max1)` |

**Output:**

4

**Explanation:**

For the given array one of the subarrays having maximum gcd is[3, 5] which has gcd 4.

**Example 2:**

## Python3

`import` `math` ` ` `# input list` `List` `=` `[` `3` `, ` `7` `, ` `2` `, ` `9` `, ` `18` `, ` `5` `, ` `1` `, ` `13` `]` ` ` `max1 ` `=` `0` `for` `i ` `in` `range` `(` `len` `(` `List` `)` `-` `1` `):` ` ` ` ` `# use math.gcd() function` ` ` `gcd1 ` `=` `math.gcd(` `List` `[i], ` `List` `[i ` `+` `1` `])` ` ` `if` `(gcd1>max1):` ` ` `max1 ` `=` `gcd1` ` ` `# print max1` `# as the result` `print` `(max1)` |

**Output:**

9

**Explanation:**

For the given array one of the subarrays having maximum gcd is[4, 5] which has gcd 9.

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