## How do you find the first index of an array?

#### Given an array of length N and an integer x, you need to find and return the first index of integer x present in the array. Return -1 if it is not present in the array.

#### The first index means, the index of the first occurrence of x in the input array.

#### Do this recursively. Indexing in the array starts from 0.

##### Input Format :

```
Line 1 : An Integer N i.e. size of array
Line 2 : N integers which are elements of the array, separated by spaces
Line 3 : Integer x
```

##### Output Format :

```
first index or -1
```

##### Constraints :

#### 1 <= N <= 10^3

##### Sample Input :

```
4
9 8 10 8
8
```

##### Sample Output :

`1`

## Solution in Java

```
//Main function
import java.util.Scanner;
public class Runner {
static Scanner s = new Scanner(System.in);
public static int[] takeInput(){
int size = s.nextInt();
int[] input = new int[size];
for(int i = 0; i < size; i++){
input[i] = s.nextInt();
}
return input;
}
public static void main(String[] args) {
int[] input = takeInput();
int x = s.nextInt();
System.out.println(Solution.firstIndex(input, x));
}
}
//Solution by technoname.com
public class Solution {
public static int firstIndex(int input[], int x) {
return ans(input,x,0);
}
public static int ans(int input[],int x,int startIndex)
{
int n=input.length;
if(startIndex==n)
{
return -1;
}
if(x==input[startIndex])
{
return startIndex;
}
return ans(input,x,startIndex+1);
}
}
```

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