#D3568. Bachgold Problem

    ID: 2961 Type: Default 1000ms 256MiB

Bachgold Problem

Bachgold Problem

Bachgold problem is very easy to formulate. Given a positive integer n represent it as a sum of maximum possible number of prime numbers. One can prove that such representation exists for any integer greater than 1.

Recall that integer k is called prime if it is greater than 1 and has exactly two positive integer divisors — 1 and k.

Input

The only line of the input contains a single integer n (2 ≤ n ≤ 100 000).

Output

The first line of the output contains a single integer k — maximum possible number of primes in representation.

The second line should contain k primes with their sum equal to n. You can print them in any order. If there are several optimal solution, print any of them.

Examples

Input

5

Output

2 2 3

Input

6

Output

3 2 2 2

inputFormat

Input

The only line of the input contains a single integer n (2 ≤ n ≤ 100 000).

outputFormat

Output

The first line of the output contains a single integer k — maximum possible number of primes in representation.

The second line should contain k primes with their sum equal to n. You can print them in any order. If there are several optimal solution, print any of them.

Examples

Input

5

Output

2 2 3

Input

6

Output

3 2 2 2

样例

6
3

2 2 2

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