import java.io.*;
class PalPrime
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
int x;
void inputData(int X)throws IOException
{
x=X;
}
int Pal(int y)
{
int a=y,b=0,rev=0;
while(a>0)
{
b=a%10;
rev=rev*10+b;
a=a/10;
}
if (rev==y)
return 1;
else
return 2;
}
boolean Prime(int m)
{
int c=0;
for(int i=1;i<=m;i++)
{
if (m%i==0)
c++;
}
if (c==2)
return true;
else
return false;
}
void main()throws IOException
{
System.out.println("Enter a 4 digit no");
int X=Integer.parseInt(br.readLine());
inputData(X);
System.out.println("Enter the same no. again");
int y1=Integer.parseInt(br.readLine());
Pal(y1);
System.out.println("Enter the same no. again");
int m1=Integer.parseInt(br.readLine());
Prime(m1);
if (Pal(y1)==1 && Prime(m1)==true)
System.out.println(x+" is a Pal-Prime No.");
else
System.out.println(x+" is not a Pal-Prime No.");
}
}
Find a prime number, add 2 to the number. Check if the new number is prime. IE : 3 is prime. 3+2 =5. 5 is prime. (3,5) are twin primes.
29 is a prime number, meaning it has no smaller factors. For any number up to 120, to check whether it is prime or not, it is sufficient to check whether it is divisible by the first four prime numbers (2, 3, 5 and 7).
You just have to work out it,take each number below it and check whether it is prime or not.
It is 29 because 29*23 = 667
You can write out this algorithm. This will then be programmed into the device to make determining prime numbers easier.
You can check each individual number, whether it is a prime number. For numbers below 100, it is enough to check whether they are divisible by 2, by 3, by 5, and by 7. If a number is divisible by none of these, it is a prime number.
First write a program to generate the prime number. After one prime number was generated, divide the big int number by the prime number. If the remainder is zero then quotient is the second prime number ( also it is important to check whether the quotient is prime number or not because sometimes you will get wrong answer). Repeat the process until you get the result.
Find a prime number, add 2 to the number. Check if the new number is prime. IE : 3 is prime. 3+2 =5. 5 is prime. (3,5) are twin primes.
29 is a prime number, meaning it has no smaller factors. For any number up to 120, to check whether it is prime or not, it is sufficient to check whether it is divisible by the first four prime numbers (2, 3, 5 and 7).
You just have to work out it,take each number below it and check whether it is prime or not.
A number is prime if it only has two distinct factors.
It is 29 because 29*23 = 667
You can write out this algorithm. This will then be programmed into the device to make determining prime numbers easier.
Take each number in turn, call it "n", and check whether it has any factors f, such that 1 < f < n. If it doesn't, it is a prime number.Take each number in turn, call it "n", and check whether it has any factors f, such that 1 < f < n. If it doesn't, it is a prime number.Take each number in turn, call it "n", and check whether it has any factors f, such that 1 < f < n. If it doesn't, it is a prime number.Take each number in turn, call it "n", and check whether it has any factors f, such that 1 < f < n. If it doesn't, it is a prime number.
You take two consecutive odd numbers and check both of them to see whether they are prime or not.
[object Object]
#include<iostream.h> #include<conio.h> void prime(int n) { clrscr(); int num; cout<<"enter the numbers"<<endl; cin>>num; prime(num); getch(); } void prime(int n) { int prime=1,i; for(i=2;i<=n/2;i++) if(n%i==1) prime=0; if(prime==1) cout<<"the number"<<n>>"is prime"; else cout<<"the number"<<n<<"is not prime"; }