Problem
Given an array of numbers, rearrange them in-place so that even numbers appear before odd ones.
Example
{
"numbers": [1, 2, 3, 4]
}
Output:
[4, 2, 3, 1]
The order within the group of even numbers does not matter; same with odd numbers. So the following are also correct outputs: [4, 2, 1, 3], [2, 4, 1, 3], [2, 4, 3, 1].
Solution
function swap(arr, i, j) {
var temp = arr[i];
arr[i] = arr[j];
arr[j] = temp;
}
function segregate_evens_and_odds(numbers) {
// Write your code here.
//Initialize two index variables left and right
var j = -1, i=0;
while (i != numbers.length) {
//If even number swap odd with even
if(numbers[i]%2 == 0) {
j++;
swap(numbers, j, i);
}
i++;
}
return numbers;
}
Time and Space Complexity
Time Complexity : O(n)
Space Complexity: O(n)
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