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# Find the total number of composite factor for a given number

• Last Updated : 26 Apr, 2021

Given an integer N, the task is to find the total number of composite factors of N. Composite factors of a number are the factors which are not prime.
Examples:

Input: N = 24
Output:
1, 2, 3, 4, 6, 8, 12 and 24 are the factors of 24.
Out of which only 4, 6, 8, 12 and 24 are composites.
Input: N = 100
Output:

Approach:

• Find all the factors of N and store it in a variable totalFactors
• Find all the prime factors of N and store it in a variable primeFactors
• Now, total composite factors will be totalFactors – primeFactors – 1 (1 is subtracted because 1 is neither prime nor composite).

Below is the implementation of the above approach:

## C++

 `// C++ implementation of the approach``#include ``using` `namespace` `std;` `// Function to return the count``// of prime factors of n``int` `composite_factors(``int` `n)``{``    ``int` `count = 0;``    ``int` `i, j;` `    ``// Initialise array with 0``    ``int` `a[n + 1] = { 0 };``    ``for` `(i = 1; i <= n; ++i) {``        ``if` `(n % i == 0) {` `            ``// Stored i value into an array``            ``a[i] = i;``        ``}``    ``}` `    ``// Every non-zero value at a[i] denotes``    ``// that i is a factor of n``    ``for` `(i = 2; i <= n; i++) {``        ``j = 2;``        ``int` `p = 1;` `        ``// Find if i is prime``        ``while` `(j < a[i]) {``            ``if` `(a[i] % j == 0) {``                ``p = 0;``                ``break``;``            ``}``            ``j++;``        ``}` `        ``// If i is a factor of n``        ``// and i is not prime``        ``if` `(p == 0 && a[i] != 0) {``            ``count++;``        ``}``    ``}` `    ``return` `count;``}` `// Driver code``int` `main()``{``    ``int` `n = 100;` `    ``cout << composite_factors(n);` `    ``return` `0;``}`

## Java

 `// Java implementation of the approach``import` `java.util.*;` `class` `Gfg``{` `// Function to return the count``// of prime factors of n``public` `static` `int` `composite_factors(``int` `n)``{``    ``int` `count = ``0``;``    ``int` `i, j;` `    ``// Initialise array with 0``    ``int``[] a=``new` `int``[n+``1``];``    ``for``( i = ``0``; i < n; i++)``    ``{``        ``a[i]=``0``;``    ``}``    ``for` `(i = ``1``; i <= n; ++i)``    ``{``        ``if` `(n % i == ``0``)``        ``{` `            ``// Stored i value into an array``            ``a[i] = i;``        ``}``    ``}` `    ``// Every non-zero value at a[i] denotes``    ``// that i is a factor of n``    ``for` `(i = ``2``; i <= n; i++)``    ``{``        ``j = ``2``;``        ``int` `p = ``1``;` `        ``// Find if i is prime``        ``while` `(j < a[i])``        ``{``            ``if` `(a[i] % j == ``0``)``            ``{``                ``p = ``0``;``                ``break``;``            ``}``            ``j++;``        ``}` `        ``// If i is a factor of n``        ``// and i is not prime``        ``if` `(p == ``0` `&& a[i] != ``0``)``        ``{``            ``count++;``        ``}``    ` `}``    ``return` `count;``}`  `// Driver code``public` `static` `void` `main(String[] args)``{``    ``int` `n = ``100``;``    ` `    ``System.out.println(composite_factors(n));` `}``}` `// This code is contributed by nidhi16bcs2007`

## Python3

 `# Python3 implementation of the approach` `# Function to return the count``# of prime factors of n``def` `composite_factors(n) :` `    ``count ``=` `0``;``    ` `    ``# Initialise array with 0``    ``a ``=` `[``0``]``*``(n ``+` `1``) ;``    ` `    ``for` `i ``in` `range``(``1``, n ``+` `1``) :``        ``if` `(n ``%` `i ``=``=` `0``) :` `            ``# Stored i value into an array``            ``a[i] ``=` `i;` `    ``# Every non-zero value at a[i] denotes``    ``# that i is a factor of n``    ``for` `i ``in` `range``(``2``,n ``+` `1``) :``        ``j ``=` `2``;``        ``p ``=` `1``;` `        ``# Find if i is prime``        ``while` `(j < a[i]) :``            ``if` `(a[i] ``%` `j ``=``=` `0``) :``                ``p ``=` `0``;``                ``break``;``                ` `            ``j ``+``=` `1``;`  `        ``# If i is a factor of n``        ``# and i is not prime``        ``if` `(p ``=``=` `0` `and` `a[i] !``=` `0``) :``            ``count ``+``=` `1``;` `    ``return` `count;`  `# Driver code``if` `__name__ ``=``=` `"__main__"` `:` `    ``n ``=` `100``;` `    ``print``(composite_factors(n));``    ` `# This code is contributed by AnkitRai01`

## C#

 `// C# implementation of the approach``using` `System;` `class` `GFG``{` `// Function to return the count``// of prime factors of n``static` `int` `composite_factors(``int` `n)``{``    ``int` `count = 0;``    ``int` `i, j;` `    ``// Initialise array with 0``    ``int``[] a = ``new` `int``[n + 1];``    ``for``( i = 0; i < n; i++)``    ``{``        ``a[i]=0;``    ``}``    ``for` `(i = 1; i <= n; ++i)``    ``{``        ``if` `(n % i == 0)``        ``{` `            ``// Stored i value into an array``            ``a[i] = i;``        ``}``    ``}` `    ``// Every non-zero value at a[i] denotes``    ``// that i is a factor of n``    ``for` `(i = 2; i <= n; i++)``    ``{``        ``j = 2;``        ``int` `p = 1;` `        ``// Find if i is prime``        ``while` `(j < a[i])``        ``{``            ``if` `(a[i] % j == 0)``            ``{``                ``p = 0;``                ``break``;``            ``}``            ``j+=1;``        ``}` `        ``// If i is a factor of n``        ``// and i is not prime``        ``if` `(p == 0 && a[i] != 0)``        ``{``            ``count += 1;``        ``}` `}``    ``return` `count;``}`  `// Driver code``public` `static` `void` `Main()``{``    ``int` `n = 100;` `    ``Console.WriteLine(composite_factors(n));``}``}` `// This code is contributed by mohit kumar 29`

## Javascript

 ``
Output:
`6`

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