I am very beginner on Java, still getting passion about. I have been given this exercise: "Write a simulator program that flips a coin: One thousand times then prints out how many time you get tails and how many times you get heads" That is what i have tried to do so far.
import java.util.Random;
import java.util.regex.Pattern;
public class coin {
public static void main( String [] args ) {
Random r = new Random();
Pattern tail = Pattern.compile("Tail+");
Pattern head = Pattern.compile("Head+");
String flips = "";
for (int i = 0; i < 1000; i++) {
flips += r.nextInt(100) % 2 == 0 ? "Head" : "Tail";
}
String[] heads = head.split( flips );
String[] tails = tail.split( flips );
//Display
System.out.println("Times head was flipped:" + heads.length);
System.out.println("Times tail was flipped:" + tails.length);
}
}
The program seems to be working, but it is giving me always an almost pair amount of heads and tails, which the total exceed 1000, at least by 1 or more. Please, someone has any solution of this? Where am I wrong? Thanks
A coin has two sides, so I really don't see why you would ask the random generator to generate a number between 0 and 100 (exclusive). Between 0 and 2 (exclusive) would be much more logical.
Also, you're being asked to count. Appending strings and then splitting to get the final value is quite a complex and inefficient way to count. You should use an integer instead. Each time you get a 1 from your random, increment a counter. In the end, you have the number of times 1 was returned, and the number of 0 is thus 1000 - this number.
Random r = new Random();
int heads = 0;
for (int i = 0; i < 1000; i++) {
int side = random.nextInt(2);
if (side == 1) {
heads++;
}
}
System.out.println("Times head was flipped:" + heads);
System.out.println("Times tail was flipped:" + (1000 - heads));
It could even be simplified to the follwoing (although this simplification makes the code a bit harder to understand):
Random r = new Random();
int heads = 0;
for (int i = 0; i < 1000; i++) {
heads += random.nextInt(2);
}
System.out.println("Times head was flipped:" + heads);
System.out.println("Times tail was flipped:" + (1000 - heads));
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