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Given a number N, find least prime factors for all numbers from 1 to N. The least prime factor of an integer N is the smallest prime number that divides it.

**Note : **The least prime factor of all even numbers is 2. A prime number is its own least prime factor (as well as its own greatest prime factor).1 needs to be printed for 1.â€‹

**Example 1:**

**Input**: N = 6
**Output:** [1, 2, 3, 2, 5, 2]
**Explanation**: least prime factor of 1 = 1,
least prime factor of 2 = 2,
least prime factor of 3 = 3,
least prime factor of 4 = 2,
least prime factor of 5 = 5,
least prime factor of 6 = 2.
So answer is[1, 2, 3, 2, 5, 2].

**Example 2:**

**Input: **N = 4
**Output: **[1, 2, 3, 2]
**Explanation**: least prime factor of 1 = 1,
least prime factor of 2 = 2,
least prime factor of 3 = 3,
least prime factor of 4 = 2.
So answer is[1, 2, 3, 2].

**Your Task: **

You dont need to read input or print anything. Complete the function **leastPrimeFactor() **which takes N as input parameter and returns a list of integers containing all the least prime factor of each numbers from 1 to N.

**Expected Time Complexity:** O(NlogN)

**Expected Auxiliary Space:** O(N)

**Constraints:**

2<= n <=10^{3}

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Least Prime Factor

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