Problem Description
Given a number N check if it’s a prime number.
Solution
The main this to remember here is that we need to check only till square root of N, because if i is a factor of N, N/i will also be a factor of N. If we get any 1 factor, return false.
1
2
3
4
5
6
7
8
9
10
static boolean isPrime(int n){
for(int i=2; i*i<=n; i++){ //We can check till root N only. If i is a factor, N/i will also be a factor.
if(n%i == 0){
return false;
}
}
return true;
}