Given two integers, A and B, the task is to find whether it is possible to make A equal to B if you are allowed to subtract a prime number P any number of times from A.
Input: A = 10, B = 4
Let P = 2 and after subtracting it
three times from A
Input: A = 41, B = 40
Approach: The key observation in the problem is we have to represent the number A as
, As we know every number is divisible by some prime number except 1. Therefore if we find the difference of the number
and if the difference is greater than 1 then both the number can be made equal by subtracting a prime number X times from A.
Below is the implementation of the above approach:
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- Check if a number is Prime, Semi-Prime or Composite for very large numbers
- Check if a prime number can be expressed as sum of two Prime Numbers
- Check if a number is divisible by all prime divisors of another number
- Check if N is a Balanced Prime number or not
- Check whether N is a Dihedral Prime Number or not
- Check whether a number is circular prime or not
- Check if a number is a Pythagorean Prime or not
- Check whether the given number is Wagstaff prime or not
- Check if a number is Primorial Prime or not
- Check if the first and last digit of number N is prime and their sum is less than K
- C Program to Check Whether a Number is Prime or not
- Check if a number is Full Prime
- Check a number for Permutable Prime
- Check if a number is Quartan Prime or not
- Check if N is a Weak Prime number or not
- Check whether a number is Good prime or not
- Check if the number is a Prime power number
- Check if there exists a number with X factors out of which exactly K are prime
- Check if a number can be written as a sum of 'k' prime numbers
- Check if all Prime factors of number N are unique or not
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