Twin prime numbers are two prime numbers whose difference is 2, and both the numbers are prime numbers.
If both the numbers are prime but the difference is not 2, then the pair of the numbers are not twin prime.
The twin prime numbers are (3, 5), (5, 7), (11, 13) etc.
But (2, 3), (7, 11) these pairs are not twin prime as the difference between two is not 2.
INPUT: Two Numbers
OUTPUT: Whether the numbers are twin prime or not
PROCESS:
Step 1: [Taking the inputs]
Read m, n
Step 2: [Checking for ‘twin prime’]
Set c<-0
[Checking for twin prime]
If absolute value of (m-n)=2 then
[Checking if m is a prime number]
For i=1 to m repeat
If m mod i=0 then
Set c<-c+1
[End of ‘if’]
[End of ‘for’ loop]
[If the 1st number is prime then check for another number]
If c=2 then
Set c<-0
For i=1 to n repeat
If n mod i=0 then
Set c<-c+1
[End of ‘if’]
[End of ‘for’ loop]
[Checking if n is a prime number]
If c=2 then
Print "The numbers are twin prime"
[If the 2nd number is not prime]
Else
Print "The numbers are not twin prime"
[End of ‘if-else’]
[End of ‘if’]
[If the 1st number is not prime]
Else
Print "The numbers are not twin prime"
[End of ‘else’]
[End of ‘if’]
[If the gap is not 2]
Else
Print "The numbers are not twin prime"
[End of ‘Else’]
Step 3: Stop.
for(i=1;i<=m;i++)-------------------------------------O(m)
{
if(m%i==0)----------------------------------O(1)
c++;
}
//if the 1st number is prime then check for another number
if(c==2)--------------------------------------------------O(1)
{
c=0;
for(i=1;i<=n;i++)----------------------------O(n)
{
if(n%i==0)--------------------------O(1)
c++;
}
//checking if n is a prime number
if(c==2)----------------------------------------O(1)
printf("The numbers are twin prime");
//if the 2nd number is not prime
else
printf("The numbers are not twin prime");
}
//if the 1st number is not prime
else
printf("The numbers are not twin prime");
The time complexity of this program is O(m+n) where ‘m’ is the first number and ‘n’ is the second number.
The space complexity of this program is O(1) as it requires a constant number of memory spaces for any given input.