# Count numbers which can be represented as sum of same parity primes

Given an arr[] of positive integers you have to count how many numbers can be represented as sum of same parity prime numbers(can be same)

**Examples:**

Input : arr[] = {1, 3, 4, 6} Output : 2 4 = 2+2, 6 = 3+3 Input : arr[] = {4, 98, 0, 36, 51} Output : 3

1. If two numbers of same parity are added then they would be always even, so all odd numbers in the array can never contribute to answer.

2. Talking about 0 and 2 both cannot be represented by sum of same parity prime numbers.

3. Rest of all numbers will contribute to the answer (Refer https://www.geeksforgeeks.org/program-for-goldbachs-conjecture-two-primes-with-given-sum/)

So, we have to just iterate over the entire array and find out number of even elements not equal to 0 and 2.

## C++

`#include <bits/stdc++.h> ` `using` `namespace` `std; ` ` ` `// Function to calculate count ` `int` `calculate(` `int` `* array, ` `int` `size) ` `{ ` ` ` `int` `count = 0; ` ` ` ` ` `for` `(` `int` `i = 0; i < size; i++) ` ` ` `if` `(array[i] % 2 == 0 && ` ` ` `array[i] != 0 && ` ` ` `array[i] != 2) ` ` ` `count++; ` ` ` ` ` `return` `count; ` `} ` ` ` `// Driver Code ` `int` `main() ` `{ ` ` ` `int` `a[] = { 1, 3, 4, 6 }; ` ` ` `int` `size = ` `sizeof` `(a) / ` `sizeof` `(a[0]); ` ` ` `cout << calculate(a, size); ` `} ` |

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## Java

`// Java program to Count numbers ` `// which can be represented as ` `// sum of same parity primes ` `import` `java.util.*; ` ` ` `class` `GFG ` `{ ` `// Function to calculate count ` `public` `static` `int` `calculate(` `int` `ar[], ` ` ` `int` `size) ` `{ ` ` ` `int` `count = ` `0` `; ` ` ` ` ` `for` `(` `int` `i = ` `0` `; i < size; i++) ` ` ` `if` `(ar[i] % ` `2` `== ` `0` `&& ` ` ` `ar[i] != ` `0` `&& ` ` ` `ar[i] != ` `2` `) ` ` ` `count++; ` ` ` ` ` `return` `count; ` `} ` ` ` `// Driver code ` `public` `static` `void` `main (String[] args) ` `{ ` ` ` `int` `a[] = { ` `1` `, ` `3` `, ` `4` `, ` `6` `}; ` ` ` `int` `size = a.length; ` ` ` `System.out.print(calculate(a, size)); ` `} ` `} ` ` ` `// This code is contributed ` `// by ankita_saini ` |

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## Python 3

`# Function to calculate count ` `def` `calculate(array, size): ` ` ` ` ` `count ` `=` `0` ` ` ` ` `for` `i ` `in` `range` `(size): ` ` ` `if` `(array[i] ` `%` `2` `=` `=` `0` `and` ` ` `array[i] !` `=` `0` `and` ` ` `array[i] !` `=` `2` `): ` ` ` `count ` `+` `=` `1` ` ` ` ` `return` `count ` ` ` `# Driver Code ` `if` `__name__ ` `=` `=` `"__main__"` `: ` ` ` `a ` `=` `[ ` `1` `, ` `3` `, ` `4` `, ` `6` `] ` ` ` `size ` `=` `len` `(a) ` ` ` `print` `(calculate(a, size)) ` ` ` `# This code is contributed ` `# by ChitraNayal ` |

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## C#

`// C# program to Count numbers ` `// which can be represented as ` `// sum of same parity primes ` `using` `System; ` ` ` `class` `GFG ` `{ ` `// Function to calculate count ` `public` `static` `int` `calculate(` `int` `[]ar, ` ` ` `int` `size) ` `{ ` ` ` `int` `count = 0; ` ` ` ` ` `for` `(` `int` `i = 0; i < size; i++) ` ` ` `if` `(ar[i] % 2 == 0 && ` ` ` `ar[i] != 0 && ` ` ` `ar[i] != 2) ` ` ` `count++; ` ` ` ` ` `return` `count; ` `} ` ` ` `// Driver code ` `static` `public` `void` `Main (String []args) ` `{ ` ` ` `int` `[]a = { 1, 3, 4, 6 }; ` ` ` `int` `size = a.Length; ` ` ` `Console.WriteLine(calculate(a, size)); ` `} ` `} ` ` ` `// This code is contributed ` `// by Arnab Kundu ` |

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## PHP

`<?php ` `// Function to calculate count ` `function` `calculate(&` `$array` `, ` `$size` `) ` `{ ` ` ` `$count` `= 0; ` ` ` ` ` `for` `(` `$i` `= 0; ` `$i` `< ` `$size` `; ` `$i` `++) ` ` ` `if` `(` `$array` `[` `$i` `] % 2 == 0 && ` ` ` `$array` `[` `$i` `] != 0 && ` ` ` `$array` `[` `$i` `] != 2) ` ` ` `$count` `++; ` ` ` ` ` `return` `$count` `; ` `} ` ` ` `// Driver Code ` `$a` `= ` `array` `(1, 3, 4, 6 ); ` `$size` `= sizeof(` `$a` `); ` `echo` `calculate(` `$a` `, ` `$size` `); ` ` ` `// This code is contributed ` `// by ChitraNayal ` `?> ` |

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**Output:**

2

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