## A Two-Pointers Problem

Given an array \(a\) of \(N\) integers, find the shortest length subarray that has a sum greater than or equal to \(M\).

#### Input Specification

The first line will contain \(2\) integers, \(N, M\) \((1 \le N \le 10^5, 1 \le M \le 10^9)\).

The second line will contain \(N\) integers \(a_1, a_2, \ldots, a_N\) \((0 \le a_i \le 10^9)\).

#### Output Specification

Output the shortest length subarray that has a sum greater than or equal to \(M\). If there is no subarray, print `-1`

.

#### Subtasks

##### Subtask 1 [10%]

\(N \le 100\)

##### Subtask 2 [90%]

No further constraints.

#### Sample Input

```
6 3
1 0 2 0 1 2
```

#### Sample Output

`2`

## Comments