練習問題のまとめ(一)

public static int[] createArray(int m,int n){
		int[] arr = new int[n - m + 2];
		Random random = new Random();
		for(int i = 0;i < arr.length - 1;++i)arr[i] = m + i;
		//set random display two time number in[m,n]
		arr[arr.length - 1] = random.nextInt(n - m + 1) + m;
		System.out.printf("before find num %d display two times
",arr[arr.length - 1]);
		//random array
		for(int i = 0;i < arr.length;++i){
			int index = random.nextInt(arr.length);
			//swap
			if(i != index){
				arr[i] ^= arr[index];
				arr[index] ^= arr[i];
				arr[i] ^= arr[index];
			}
		}		
		return arr;	
	}

	public static int getDisplayTwoTimesNumber(int[] arr,int m){
		for(int i = 0;i < arr.length - 1;++i) arr[arr.length - 1] += arr[i];
		return arr[arr.length - 1] - (m + m + arr.length - 2) * (arr.length - 1) / 2;
	}

	public static double calcRatio(double[] parmas,int k)
	{
		final int TOTAL_TIME = 10;
		int[] scoreArr = new int[]{8,9,10};
		int[] timeArr = new int[TOTAL_TIME];
		final int TOTAL_COUNT = (int)Math.pow(scoreArr.length, TOTAL_TIME);
		double ratio = 1,totalRatio = 0;
		for(int i = 0,sum = 0;i < TOTAL_COUNT;++i,sum = 0,ratio = 1){
			int time = i;
			for(int j = 0;j < timeArr.length;++j){				
				timeArr[j] = time % scoreArr.length;
				time /= scoreArr.length;
				sum += scoreArr[timeArr[j]];
				ratio *= parmas[timeArr[j]];
			}
			if(sum == k)totalRatio += ratio;
		}
		BigDecimal result = new BigDecimal(totalRatio).setScale(6,RoundingMode.HALF_UP);
		return result.doubleValue();
	}

public class MyStack {
    private static final int SIZE = 100;
    private int[] data = new int[SIZE];
    private int topOfArray = -1;
    private int topOfMinData = -1;
    private int size = 0;
    private int min;
    private int[] minData = new int[SIZE];
    
    public MyStack(){
        clear();
    }
    
    public void clear(){
        data = new int[SIZE];
        minData = new int[SIZE];
        topOfArray = -1;
        size = 0;
    }
    
    public void push(int x){
        data[++topOfArray] = x;
        size++;
        if(topOfArray == 0 || data[topOfArray] <= min){            
            min = data[topOfArray];
            minData[++topOfMinData] = data[topOfArray];
        }
    }
    
    public int pop(){
        size--;
        if(data[topOfArray] == min && topOfArray > 0){
            min = minData[--topOfMinData];
        }
        else if(topOfArray == 0){
            clear();
            return 0;
        }
        return data[topOfArray--];
    }
    
    public int findMin(){
        if(topOfArray == -1){
            return Integer.MAX_VALUE * (-1);
        }
        return minData[topOfMinData];
    }
    
}

public class Poker {
	private final static int CARD_COUNT = 52;
	private static String[] CARD_FLOWERS = new String[]{"Spade","Heart","Club","Diamond"};
	private static String[] CARD_VALUES = new String[]{"A","2","3","4","5","6","7","8","9",
		"10","J","Q","K"};
	private static String[] CARD_GHOSTS_FLOWERS = new String[]{"ghost","ghost"};
	private static String[] CARD_GHOSTS_VALUES = new String[]{"Small","Big"};
	
	private String flower;
	private String value;
	private int index;
	
	private static Poker[] _pokers;
	
	public String getFlower() {
		return flower;
	}
		
	public String getValue() {
		return value;
	}
	
	public int getIndex() {
		return index;
	}
	
	public Poker(String flower,String value,int index){
		this.flower = flower;
		this.value = value;
		this.index = index;
	}
	
	private static Poker[] getCardsInstance(){
		if(_pokers != null){
			return _pokers;
		}
		_pokers = new Poker[CARD_COUNT];
		for(int i = 0;i < CARD_FLOWERS.length;++i){
			for(int j = 0;j < CARD_VALUES.length;++j){
				int index = i * CARD_VALUES.length + j;
				_pokers[index] = new Poker(CARD_FLOWERS[i], CARD_VALUES[j], index + 1);
			}
		}
		for(int i = CARD_GHOSTS_FLOWERS.length - 1;i >= 0;--i){
			int index = CARD_COUNT - i;
			_pokers[index - 1] = new Poker(CARD_GHOSTS_FLOWERS[i], CARD_GHOSTS_VALUES[i], index);
		}
		return _pokers;
	}
	
	public static Poker[] shufflingCards(){
		Random random = new Random();
		Poker[] pokers = getCardsInstance();
		for(int i = 0;i < pokers.length;++i){
			int index = random.nextInt(pokers.length);
			if(i != index){
				Poker cardTemp = pokers[i];
				pokers[i] = pokers[index];
				pokers[index] = cardTemp;
			}
		}
		return pokers;
	}
	
	public String toString(){
		return this.flower + this.value;
	}
	
	public static void displayPlayerCards(Poker[] poker){
		final int PLAYERS = 4;
		for(int i = 1;i <= poker.length;++i){
			System.out.print(poker[i - 1].toString() + " ");
			if(i % (poker.length / PLAYERS) == 0)System.out.println();
		}
	}
}