# Program to print factors of a number in pairs

Given a number n, the task of the programmer is to print the factors of the number in such a way that they occur in pairs. A pair signifies that the product of the pair should result in the number itself;

Examples:

Input : 24 Output : 1*24 2*12 3*8 4*6 Input : 50 Output : 1*50 2*25 5*10

The simplest approach for this program is that we run a loop from 1 to the square root of N and print and print ‘i’ and ‘N%i’ if the number N is dividing ‘i’.

The mathematical reason why we run the loop till square root of N is given below:

If **a*b = N** where **1 < a ≤ b < N**

N = ab ≥ a^2 ⇔ a^2 ≤ N ⇔ a ≤ √N

## C++

`// CPP program to print prime factors in ` `// pairs. ` `#include <iostream> ` `using` `namespace` `std; ` ` ` `void` `printPFsInPairs(` `int` `n) ` `{ ` ` ` `for` `(` `int` `i = 1; i * i <= n; i++) ` ` ` `if` `(n % i == 0) ` ` ` `cout << i << ` `"*"` `<< n / i << endl; ` `} ` ` ` `// Driver code ` `int` `main() ` `{ ` ` ` `int` `n = 24; ` ` ` `printPFsInPairs(n); ` ` ` `return` `0; ` `} ` |

*chevron_right*

*filter_none*

## Java

`// Java program to print prime factors in ` `// pairs. ` `public` `class` `GEE { ` ` ` ` ` `static` `void` `printPFsInPairs(` `int` `n) ` ` ` `{ ` ` ` `for` `(` `int` `i = ` `1` `; i * i <= n; i++) ` ` ` `if` `(n % i == ` `0` `) ` ` ` `System.out.println(i + ` `"*"` `+ n / i); ` ` ` `} ` ` ` ` ` `// Driver code ` ` ` `public` `static` `void` `main(String[] args) ` ` ` `{ ` ` ` ` ` `int` `n = ` `24` `; ` ` ` `printPFsInPairs(n); ` ` ` `} ` `} ` |

*chevron_right*

*filter_none*

## C#

`// C# program to print prime factors in ` `// pairs. ` `using` `System; ` `public` `class` `GEE { ` ` ` ` ` `static` `void` `printPFsInPairs(` `int` `n) ` ` ` `{ ` ` ` `for` `(` `int` `i = 1; i * i <= n; i++) ` ` ` `if` `(n % i == 0) ` ` ` `Console.Write(i + ` `"*"` `+ n / i + ` `"\n"` `); ` ` ` `} ` ` ` ` ` `// Driver code ` ` ` `public` `static` `void` `Main() ` ` ` `{ ` ` ` ` ` `int` `n = 24; ` ` ` `printPFsInPairs(n); ` ` ` `} ` `} ` |

*chevron_right*

*filter_none*

## Python 3

`# Python 3 program to print prime factors in ` `# pairs. ` ` ` `def` `printPFsInPairs(n): ` ` ` `for` `i ` `in` `range` `(` `1` `, ` `int` `(` `pow` `(n, ` `1` `/` `2` `))` `+` `1` `): ` ` ` `if` `n ` `%` `i ` `=` `=` `0` `: ` ` ` `print` `(` `str` `(i) ` `+` `"*"` `+` `str` `(` `int` `(n ` `/` `i))) ` ` ` `# Driver code ` `n ` `=` `24` `printPFsInPairs(n) ` |

*chevron_right*

*filter_none*

## PHP

`<?php ` `// PHP program to print prime factors in ` `// pairs. ` ` ` `function` `printPFsInPairs(` `$n` `) ` `{ ` ` ` `for` `(` `$i` `= 1; ` `$i` `*` `$i` `<= ` `$n` `; ` `$i` `++) ` ` ` `if` `(` `$n` `% ` `$i` `== 0) ` ` ` `echo` `$i` `.` `"*"` `. ` `$n` `/ ` `$i` `.` `"\n"` `; ` `} ` ` ` `// Driver code ` `$n` `= 24; ` `printPFsInPairs(` `$n` `); ` `return` `0; ` `?> ` |

*chevron_right*

*filter_none*

**Output:**

1*24 2*12 3*8 4*6

## Recommended Posts:

- Efficient program to print the number of factors of n numbers
- Efficient program to print all prime factors of a given number
- C Program for efficiently print all prime factors of a given number
- Java Program for efficiently print all prime factors of a given number
- Find number of factors of N when location of its two factors whose product is N is given
- Print all numbers whose set of prime factors is a subset of the set of the prime factors of X
- Print all prime factors and their powers
- Print all combinations of factors (Ways to factorize)
- Program to print multiplication table of a number
- Program to print 'N' alphabet using the number pattern from 1 to n
- Program to print triangular number series till n
- Number which has the maximum number of distinct prime factors in the range M to N
- Super Ugly Number (Number whose prime factors are in given set)
- Queries on sum of odd number digit sums of all the factors of a number
- Number with maximum number of prime factors

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.