# Separate odd and even numbers in an array

#### Problem :

Given an array of integers, you need to segregate odd and even numbers in an array.
Please note : Order of elements can be changed.
For example:

#### Algorithm:

Lets say array is arr[]

• Initialise two index variable , left=0 and right=arr.length-1
• Increment left variable until you get odd number
• Decrement right variable until you get even number.
• If left < right, swap arr[left] and arr[right]
• In the end, you will see that you have even numbers on left side and odd numbers on right side.

### Java code to separate odd and even numbers in an array :

when you run above program, you will get below output:

import_contacts

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1. Praveen says:

Thanks. Very helpful but how can we merge two unsorted arrays and also find smaller number of that unsorted array

2. test says:

Below is better approach :
while(low<=high){
if(arr[low]%2!=0){
if(arr[high]%2==0) {
int temp = arr[low];
arr[low] = arr[high];
arr[high] = temp;
low++;
high–;
}else{
high–;
}
}else{
low++;
}

}

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