Given an array of numbers, find the maximum sum of any contiguous subarray of the array.

For example, given the array [34, -50, 42, 14, -5, 86], the maximum sum would be 137, since we would take elements 42, 14, -5, and 86.

Given the array [-5, -1, -8, -9], the maximum sum would be -1.

Follow up: Do this in O(N) time.

Detailed explanation ( Input/output format, Notes, Images )

**Input format:**
```
The first line of input contains size of array, which is denoted by N and second line of input contains N space separated integers.
```

**Output format:**
```
The first and only line of output should print the maximum subarray sum, as described in the description.
```

##### Sample Input 1:

```
4 1
1 2 3 4
```

##### Sample Output 1:

```
4
```

##### Sample Input 2:

```
6 2
2 7 3 6 7 7
```

##### Sample Output 2:

```
14
```

#### Explanation for Sample Output 2:

```
There are 5 subarrays of size 2 in this array. They are {2, 7}, {7, 3}, {3, 6}, {6, 7}, {7, 7}. Since the subarray {7, 7} has the maximum sum among all the subarrays, the output will be 7 + 7 = 14
```