import java.util.Random;

public final class AIMath
{
	public static Random rand=new Random(System.currentTimeMillis());
	public static int getRandomInt(int max)
	{
		return (int)(getRandomFloat()*(max+1));
	}
	public static final int chooseItem(float[] list)
	{
		float probs[]=normalize(list);
		float p=getRandomFloat();
		int i;
		for (i=0;(i<probs.length)&&(p>probs[i]);i++)
			p-=probs[i];
		if (i>=probs.length) i=probs.length-1;
		return i;
	}
	public static final int chooseItem(int[] list)
	{
		float probs[]=normalize(list);
		float p=getRandomFloat();
		int i;
		for (i=0;(i<probs.length)&&(p>probs[i]);i++)
			p-=probs[i];
		if (i>=probs.length) i=probs.length-1;
		return i;
	}
	public static final float[] normalize(float[] vec)
	{
		return scale(vec,1/summation(vec));
	}
	public static final float[] normalize(int [] vec)
	{
		return scale(vec,1/(float)summation(vec));
	}
	public static final float summation(float[] vec)
	{
		float sum=0;
		for (int i=0;i<vec.length;i++)
			sum+=vec[i];
		return sum;
	}
	public static final int summation(int[] vec)
	{
		int sum=0;
		for (int i=0;i<vec.length;i++)
			sum+=vec[i];
		return sum;
	}
	public static float average(float[] vec)
	{
		return summation(vec)/(vec.length);
	}
	public static int average(int[] vec)
	{
		return (int)Math.rint(summation(vec)/(double)vec.length);
	}
	public static float[] scale(float[] vec, float scalar)
	{
		float ret[] = new float[vec.length];
		for (int i=0;i<vec.length;i++)
			ret[i]=vec[i]*scalar;
		return ret;
	}
	public static float[] scale(int[] vec, float scalar)
	{
		float ret[] = new float[vec.length];
		for (int i=0;i<vec.length;i++)
			ret[i]=vec[i]*scalar;
		return ret;
	}
	public static int[] scale(int[] vec, int scalar)
	{
		int ret[] = new int[vec.length];
		for (int i=0;i<vec.length;i++)
			ret[i]=vec[i]*scalar;
		return ret;
	}
	public static float getRandomFloat()
	{
		return (float)rand.nextDouble();
	}
	public static float minimum(float[] vec)
	{
		if (vec.length!=0)
		{
			float min=vec[0];
			for (int i=0;i<vec.length;i++)
				if (vec[i]<min) min=vec[i];
			return min;
		}
		return 0;
	}
	public static int minimum(int[] vec)
	{
		if (vec.length!=0)
		{
			int min=vec[0];
			for (int i=0;i<vec.length;i++)
				if (vec[i]<min) min=vec[i];
			return min;
		}
		return 0;
	}
	public static float maximum(float[] vec)
	{
		if (vec.length!=0)
		{
			float max=vec[0];
			for (int i=0;i<vec.length;i++)
				if (vec[i]>max) max=vec[i];
			return max;
		}
		return 0;
	}
	public static int maximum(int[] vec)
	{
		if (vec.length!=0)
		{
			int max=vec[0];
			for (int i=0;i<vec.length;i++)
				if (vec[i]>max) max=vec[i];
			return max;
		}
		return 0;
	}
	public static int indexOfMinimum(float[] vec)
	{
		float prev = vec[0];
		int index = 0;
		for (int i=1; i<vec.length; i++)
		{
			if (prev < vec[i])
			{
				prev=vec[i];
				index=i;
			}
		}
		return index;
	}
	public static int indexOfMinimum(int[] vec)
	{
		int prev = vec[0];
		int index = 0;
		for (int i=1; i<vec.length; i++)
		{
			if (prev < vec[i])
			{
				prev=vec[i];
				index=i;
			}
		}
		return index;
	}
	public static int indexOfMaximum(float[] vec)
	{
		float prev = vec[0];
		int index = 0;
		for (int i=1; i<vec.length; i++)
		{
			if (prev > vec[i])
			{
				prev=vec[i];
				index=i;
			}
		}
		return index;
	}
	public static int indexOfMaximum(int[] vec)
	{
		int prev = vec[0];
		int index = 0;
		for (int i=1; i<vec.length; i++)
		{
			if (prev > vec[i])
			{
				prev=vec[i];
				index=i;
			}
		}
		return index;
	}

}