# Java program to display prime numbers from 1 to 100

Let’s learn java program to display prime numbers from 1 to 100.

## Java program to display prime numbers from 1 to 100

Prime number program in java is most common java interview question.

A prime number is one which is divisible by 1 and itself.

Here’s the java program to display prime numbers from 1 to 100.

```public class PrimeNumbersFrom1To100
{
public static void main(String[] args)
{
int maxNumber = 100;
boolean prime = true;
for(int a = 1; a <= maxNumber; a++)
{
prime = checkPrime(a);
if(prime)
{
}
}
System.out.println("Display prime numbers from 1 to " + maxNumber + ": ");
}
public static boolean checkPrime(int number)
{
int remainder;
for(int a = 2; a <= number / 2; a++)
{
remainder = number % a;
// if remainder is equal to 0 then number is not prime
if(remainder == 0)
{
return false;
}
}
return true;
}
}

```

Output:

Display prime numbers from 1 to 100:
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97

Similarly we can display prime numbers from 1 to n.

Here’s the java program to display prime numbers from 1 to n or prime number program in java using scanner.

```import java.util.Scanner;
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
int a = 0;
int number = 0;
System.out.println("Please enter the value of n : ");
int n = sc.nextInt();
for(a = 1; a <= n; a++)
{
int count = 0;
for(number = a; number >= 1; number--)
{
if(a % number == 0)
{
count = count + 1;
}
}
if(count == 2)
{
}
}
System.out.println("Java program to display prime numbers from 1 to n : ");
sc.close();
}
}

```

Output:

Please enter the value of n : 200
Java program to display prime numbers from 1 to n :
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97 101 103 107 109 113 127 131 137 139 149 151 157 163 167 173 179 181 191 193 197 199

Also read – switch statement in java

Also read – print first 10 prime numbers in java

Also read – prime number program in java using scanner

### prime number program in java using for loop

Let’s learn prime number program in java using for loop.

```public class PrimeNumberUsingForLoop
{
public static void main(String[] args)
{
int number = 73;
boolean boolFlag = false;
for(int a = 2; a <= number / 2; ++a)
{
if(number % a == 0)
{
boolFlag = true;
break;
}
}
if(!boolFlag)
{
System.out.println(number + " is a prime number.");
}
else
{
System.out.println(number + " is not a prime number.");
}
}
}

```

Output:

73 is a prime number.

#### Java program to print prime numbers from 1 to 100 using while loop

Here’s the java program to print prime numbers from 1 to 100 using while loop.

```public class PrimeNumberUsingWhileLoop
{
public static void main(String[] args)
{
int checkPrime;
int num = 1;
int count;
System.out.println("Printing prime numbers from 1 to 100 using while loop: ");
while(num <= 100)
{
count = 0;
checkPrime = 2;
while(checkPrime <= num / 2)
{
if(num % checkPrime == 0)
{
count++;
break;
}
checkPrime++;
}
if(count == 0 && num != 1)
{
System.out.print(num + " ");
}
num++;
}
}
}

```

Output:

Printing prime numbers from 1 to 100 using while loop:
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97