If numToCheck is completely divisible by another number, the output is false, and the loop is broken.īut if numToCheck is prime, the output is true. So, if the input is 15, its half is 7.5, and the loop will repeat through values 2 to 8. Hence, we must loop through just numToCheck/2. Note that no number is divisible by more than half of itself. But if the remainder is 0, the number is not prime. For example, we have to divide an input number, say 15, from values 2 to 15 and check the remainder. The main method calls the method “CheckPrime” to decide whether a number is prime or not in Java. The key method of the prime number program in Java includes a loop to check and find prime number between 1 to 100 in Java. The following section explains how to find prime number between 1 to 100 in Java. Types of Inheritance in C++ What Should You Know? How to Install Specific Version of NPM Package? Read our Popular Articles related to Software Development

Earn Executive PG Programs, Advanced Certificate Programs, or Masters Programs to fast-track your career. Learn Software Development Courses online from the World’s top Universities. Our previous algorithm does this task and appends all the prime numbers to the ArrayList. What we have to do is print all the prime numbers between the range. We’ve declared two variables lower and upper and assigning those variables with user input. In the above code, we are initializing a scanner for reading user input. Let’s build the code now! Scanner sc=new Scanner(System.in) The whole algorithm will be almost similar to the above code, the only difference we make is taking user input for the lower limit and upper limit of the range.

After running the prime number algorithm for each number we are pushing it into ArrayList if it is a prime number. Now we have two for loops first for loop is for looping over all the numbers between 1 to 100 and the second for loop is our previous prime number algorithm. In the above code, we’ve declared an ArrayList that stores all the prime numbers in the range of 1 to 100. Here’s the code to do that.Ĭheck out upGrad’s Java Bootcamp int n = 5

If the count is 2 then we can conclude that the given number is a prime, else it is not a prime. At first, we need to loop over all the numbers from 1 to N and maintain a count of numbers that properly divides the given number. Before jumping to the code, we’ll understand the algorithm to check if a number is a prime number or not.

List of prime numbers through 100