Examen JAVA 2019

// QCM: a / b / a / f / a / b / c / b / a / b / a / f

//ex2
// methode 1

import java.util.*;
public class Ex5 {
    public static void main(String[] args) {
        int[] numbers = new int[]{8,2,7,4,6,3,1};
        int sum = 0;
        int _sum = (numbers.length + 1) * (numbers.length + 2) / 2; // arithmetic sum (n+1)*n/2, n=numbers.length+1
        for(int i=0; i<numbers.length;i++)
            sum += numbers[i];

        System.out.print(_sum - sum);
    }
}

// methode 2

import java.util.*;
public class Ex5 {
    public static void main(String[] args) {
        int[] numbers = new int[]{8,2,7,4,6,3,1};
        ArrayList n = new ArrayList();
        for(int i=0; i<numbers.length;i++)
            n.add(numbers[i]);

        for(int i=1; i<(int)Collections.max(n);i++)
            if(!n.contains(i))
                System.out.print(i);
    }
}



// ex3

2
-2
B
B
0
-2
A
B

// ex4
class TabPlein extends Exception{
    public String toString{
        return "tableau plein!";
    }
}
abstract class TabTrie{
    Object tab[];
    int nbrObj = 0;
    static boolean plusGrand(Object a, Object b) {
        return false;
    }
    abstract void ajouter(Object a) throws TabPlein;
    public abstract String toString();
}

class CoupleLexico{
    private int x, y;

    CoupleLexico(int x, int y){
        this.x = x;
        this.y = y;
    }

    int getX() {
        return x;
    }

    int getY() {
        return y;
    }
    public String toString() {
        return new String("("+getX()+","+getY()+")");
    }
}

public class TabTriCouple extends TabTrie {

    TabTriCouple(int n){
        tab = new CoupleLexico[n];
    }

    static boolean plusGrand(CoupleLexico a, CoupleLexico b) {
        return ( a.getX() > b.getX() ) || ( a.getX() == b.getX() && a.getY() > b.getY() );
    }

    void ajouter(Object a) throws TabPlein {
        if( nbrObj == tab.length )
            throw new TabPlein();
        int i;
        for( i=nbrObj ; i>0 ; i-- ) {
            if( plusGrand((CoupleLexico) tab[i-1],(CoupleLexico) a) ) {
                tab[i] = tab[i-1];
            }
            else
                break;
        }
        tab[i] = (CoupleLexico) a;
        nbrObj++;
    }

    public String toString() {
        String str = new String();
        CoupleLexico c;
        for( int i=0 ; i<nbrObj ; i++ ) {
            c = (CoupleLexico) tab[i];
            str += c + ", ";
        }
        return str;
    }

    public static void main(String[] args) {
        TabTriCouple c = new TabTriCouple(8);
        try {
            c.ajouter(new CoupleLexico(2, 4));
            c.ajouter(new CoupleLexico(3, 4));
            c.ajouter(new CoupleLexico(5, 2));
            c.ajouter(new CoupleLexico(4, 2));
            c.ajouter(new CoupleLexico(4, 3));
            c.ajouter(new CoupleLexico(2, 1));
            c.ajouter(new CoupleLexico(3, 5));
            System.out.println(c);
        } catch (TabPlein e) {
            e.printStackTrace();
        }
    }

}