# Climb Stairs With Minimum Moves

easy

1. You are given a number n, representing the number of stairs in a staircase. 2. You are on the 0th step and are required to climb to the top. 3. You are given n numbers, where ith element's value represents - till how far from the step you could jump to in a single move. You can of-course fewer number of steps in the move. 4. You are required to print the number of minimum moves in which you can reach the top of staircase. Note -> If there is no path through the staircase print null.

## Constraints

0 <= n <= 20 0 <= n1, n2, .. <= 20

## Format

### Input

A number n .. n more elements

### Output

A number representing the number of ways to climb the stairs from 0 to top.

## Example

Sample Input

10
3
3
0
2
1
2
4
2
0
0

### Sample Output

4

Question Video