package a0;
public class Primes {
private
static void findPrimes(int nValues) {
boolean isPrime = true;
for (int i = 2; i <=
nValues; i++) {
isPrime = true;
for (int j = 2; j < i; j++) {
if (i % j == 0) {
isPrime = false;
break;
}
}
if (isPrime) {
System.out.println(i);
}
}
}
private
static void findPrimesFaster(int nValues) {
// PLACE YOUR
IMPLEMENTATION HERE
System.out.println("The
method findPrimesFaster has not been implemented");
}
private
static void findPrimesEvenFaster(int nValues) {
// PLACE YOUR
IMPLEMENTATION HERE
System.out.println("The
method findPrimesEvenFaster has not been implemented");
}
public
static void main(String[] args) {
// Find and print all
primes between 0 and 50.
System.out.println("Running method findPrimes:");
findPrimes(50);
System.out.println("\nRunning method findPrimesFaster:");
findPrimesFaster(50);
System.out.println("\nRunning method findPrimesEvenFaster:");
findPrimesEvenFaster(50);
// Time how long it
takes to find primes.
long startTime = 0;
long endTime = 0;
System.out.print("\n\nTiming method findPrimes:");
startTime =
System.currentTimeMillis();
findPrimes(20000);
endTime =
System.currentTimeMillis();
System.out.println(" " + (endTime-startTime) + "
milliseconds");
System.out.print("\nTiming method findPrimesFaster:");
startTime =
System.currentTimeMillis();
findPrimesFaster(20000);
endTime =
System.currentTimeMillis();
System.out.println(" " + (endTime-startTime) + "
milliseconds");
System.out.print("\nTiming method findPrimesEvenFaster:");
startTime =
System.currentTimeMillis();
findPrimesEvenFaster(20000);
endTime =
System.currentTimeMillis();
System.out.println(" " + (endTime-startTime) + "
milliseconds");
System.out.print("\n\nTiming method findPrimes:");
startTime =
System.currentTimeMillis();
findPrimes(50000);
endTime =
System.currentTimeMillis();
System.out.println(" " + (endTime-startTime) + "
milliseconds");
System.out.print("\nTiming method findPrimesFaster:");
startTime =
System.currentTimeMillis();
findPrimesFaster(50000);
endTime =
System.currentTimeMillis();
System.out.println(" " + (endTime-startTime) + "
milliseconds");
System.out.print("\nTiming method findPrimesEvenFaster:");
startTime =
System.currentTimeMillis();
findPrimesEvenFaster(50000);
endTime =
System.currentTimeMillis();
System.out.println(" " + (endTime-startTime) + "
milliseconds");
}
}