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src/mior/model/DynamicArray.java 1.18 KB
1b1e928cc   glaville   initial import of...
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  package mior.model;
  
  import mcmas.core.MCMChrono;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  
  
  public class DynamicArray {
  	
  	private int[] array;
  	private int length;
  	
  	public DynamicArray() {
  		this.array = new int[1024];
  	}
  	
  	public void set(int index, int value) {
  		if (index >= array.length) {
  			this.array = Arrays.copyOf(array, index << 1); //nearestPowerOfTwo(index + 1)); 
  		}
  		
  		this.length = Math.max(length, index + 1);
  		this.array[index] = value;
  	}
  	
  	public int get(int index) {
  		return this.array[index];
  	}
  	
  	public int[] toArray() {
  		return Arrays.copyOf(array, length);
  	}
  	
  	private int nearestPowerOfTwo(int n) {
  		final int bitsize = Integer.SIZE;
  		n--;
  		
  		for (int i = 1; i <= bitsize >> 1; i <<= 1) {
  			n = n | (n >> i);
  		}
  		
  		return n + 1;
  	}
  	
  	public static void main(String[] args) {	
  		MCMChrono c = new MCMChrono("ArrayList");
  		
  		c.start();
  		
  		ArrayList<Integer> a = new ArrayList<Integer>();
  		
  		for (int i = 0; i < 10000000; i++) {
  			a.add(i);
  		}
  		
  		System.out.println(c.stop());
  		
  		c.start();
  		
  		DynamicArray b = new DynamicArray();
  		
  		for (int i = 0; i < 10000000; i++) {
  			b.set(i, i);
  		}
  		
  		System.out.println(c.stop());
  	}
  	
  }