import java.util.*;
import java.io.*;
import java.lang.Math;

public class BAMsupport
{
	static Scanner keyboard=  new Scanner(System.in);	// Create scanner object for keyboard input.


	//// I/O METHODS //		
	public static void say( String s )	{  System.out.println( s );	}
	public static void say( int i )		{  System.out.println( i );	}
	public static void say( double d )	{  System.out.println( d );	}

	public static void saywhat( String s, int what )	{  say( s + what );	}
	public static void saywhat( String s, double what )	{  say( s + what );	}

	public static int askint( String prompt )
	{
		say( prompt + " " );		// NOTE:  Not println 
		return keyboard.nextInt();
	}
	public static double askd( String prompt )
	{
		say( prompt + " " );
		return keyboard.nextDouble();
	}
	public static String asks( String prompt )
	{
		say( prompt + "..." );
		return keyboard.next();
	}
	
	//// Methods to display arrays (of various types). ////
	public static void showarray( int a[], int m ) 
		{	for (int j=0; j<m; j++ )	say( a[j] );	}
	public static void showarray( double a[], int m ) 
		{	for (int j=0; j<m; j++ )	say( a[j] );	}
	public static void showTwo( int m, double a[], double b[] ) 
		{	for (int j=0; j<m; j++ )	say( a[j]+ ",	" +b[j] );
	}
	
	public static void showEach( int m, double[]... a ) 
	{	
		String s;
		for (int j=0; j<m; j++ )
		{
			s=  "" + a[0][j];
			for (int i=1; i<a.length; i++)
			{
				s +=  ",	" + a[i][j];
			}
			say( s );
		}
	}



	//// METHODS to read into array. ////
	public static int fileToArray( String f, double[] a )
	{
		// Open file, create scanner. //
		boolean ok=false;
		File fileObject;
		Scanner inputFile = null;
		while ( ! ok )
		{
			try
			{
				fileObject=  new File( f );			// Open file.
				inputFile=  new Scanner(fileObject);
				ok = true;
			}
			catch( FileNotFoundException e)
			{
				say( "File " + f + " could not be opened" );
				f=  asks( "Enter file name:  " );		// Try again.
			}
		}

		// Read data from file. //
		int many=0;
		do {
			if ( ! inputFile.hasNext() ) { break;}		// (Break, when done,)
			a[many]=  inputFile.nextDouble();		// Read into next array element.
			many++;
		} while( many < a.length );

		inputFile.close();
		say( many );
		return many;
	}
	public static int fileToArray( double[] a )			// Read from specified file.
	{
		//// Fill array a[] from data file; return the number of values.
		
		String f=  asks( "Enter file name:  " );
		return fileToArray( f, a );
	}
	public static int fileToTwo( String f, double[] a, double[] b )
	{
		//// Fill arrays from data file; return the number of values.
		// Open file, create scanner. //
		boolean ok=false;
		File fileObject;
		Scanner inputFile = null;
		while ( ! ok )
		{
			try
			{
				fileObject=  new File( f );			// Open file.
				inputFile=  new Scanner(fileObject);
				ok = true;
			}
			catch( FileNotFoundException e)
			{
				say( "File " + f + " could not be opened" );
				f=  asks( "Enter file name:  " );		// Try again.
			}
		}

		// Read data from file. //
		int many=0;
		do {
			if ( ! inputFile.hasNext() )	{
				inputFile.nextLine(); 
				break; 
			}
			a[many]=  inputFile.nextDouble();			// Read into next array element.
			if ( ! inputFile.hasNext() )	{
				inputFile.nextLine(); 
				break; 
			}
			b[many]=  inputFile.nextDouble();			// 2nd array, too.
			many++;
		} while( many < a.length );

		inputFile.close();
		say( many );
		return many;
	}
	public static int fileToTwo( double[] a, double[] b )			// Read from specified file.
	{
		//// Fill array a[] from data file; return the number of values.
		
		String f=  asks( "Enter file name:  " );
		return fileToTwo( f, a, b );
	}
	
	public static int fileToEach( String f, double[]... a ) 
	{
		//// Fill arrays from data file; return the number of values.
		
		// Open file, create scanner. //
		boolean ok=false;
		File fileObject;
		if (f == "") f=  asks( "Enter file name:  " );
		Scanner inputFile = open( f );
		
		// Read data from file. //
		int many=0;
		do {							// For each index.
			for (int i=0; i<a.length; i++)			// For each array:
			{
				if ( ! inputFile.hasNext() )		// NO MORE DATA..
				{
					inputFile.close();
					return many;
				}
				a[i][many]=  inputFile.nextDouble();	// Read next array element.
			}// Each array.//
			many++;						// Next index.
		} while( many < a[0].length );				// (No more room in array.)

		inputFile.close();
		say( "Arrays are full." );
		return many;
	}


	//// METHOD to open a scanner file. ////
	public static Scanner open( String f )
	{
		File fileObject;
		Scanner x = null;
		boolean ok = false;
		while ( ! ok )
		{
			try
			{
				fileObject=  new File( f );			// Open file.
				x=  new Scanner(fileObject);
				ok = true;
			}
			catch( FileNotFoundException e)
			{
				say( "File " + f + " could not be opened" );
				f=  asks( "Enter file name:  " );		// Try again.
			}
		}
		return x;
	}
	public static Scanner open( )
	{
		String f=  asks( "Enter file name:  " );
		return open( f );
	}

	//// METHODS TO COPY ARRAYS (of various types). ////
	public static void copyarray( int[] to, int[] from, int m ) {		// int = int
		for (int j=0; j<m; j++ )	to[j]=  from[j];	}
	public static void copyarray( double[] to, double[] from, int m ) {	// d = d
		for (int j=0; j<m; j++ )	to[j]=  from[j];	}
	public static void copyarray( double[] to, int[] from, int m ) {	// d = i
		for (int j=0; j<m; j++ )	to[j]=  from[j];	}
	public static void copyarray( int[] to, double[] from, int m ) {	// i = d
		for (int j=0; j<m; j++ )	to[j]=  (int) from[j];	}
	


	//// CLOSED MATH FUNCTIONS:  abs, pow, etc. ////
	public static int abs( int x )				//// Integer versions //
	{
		return (x < 0) ? -x : x; 			// Return |x|
	}
	public static int pow( int x, int p )	
	{
		if (p == 0) return 1;				// x^0 is 1
		else if (p > 0) return x * pow( x, p-1 );	// x * x^(p-1)
		else 
		{
			say( "ERROR:  Negative power.  pow( " +x+ "," +p+ ")" );
			return 0;
		}
	}

	public static double abs( double x )		
	{
		return (x < 0) ? -x : x; 			// Return |x|
	}
	public static double pow( double x, int p )	
	{
		if (p == 0) return 1;			// x^0 is 1
		else if (p > 0) return x * pow( x, p-1 );		// x * x^(p-1)
		else return 1.0 / pow( x, abs(p) );		// p < 0 ... return 1 / x^|-p|
	}
	public static double pow( double x, double p )	
	{
		if (p == 0) return 1;				// x^0 is 1
		else if (p == 1) return x;			// x * x^(p-1)
		else if (p > 1) return x * pow( x, p-1 );	// x * x^(p-1)
		else if (p<0) return 1.0 / pow( x, abs(p) );	// p < 0 ... return 1 / x^|-p|
		else if (p == 0.5) return Math.sqrt( x ) ;		// Special case for sqrt.
		else	// (p is between zero and 1)
		{
			say( "SORRY, fractional powers have not yet been implemented:  pow( " +x+ "," +p+ ") will return zero." );
			return 0;	
		}
	}

}