public class SyncTest ( private int x; private int y; private synchronized void setX (int i) (x=1;) private synchronized void setY (int i) (y=1;) public void setXY(int 1)(set X(i); setY(i);) public synchronized Boolean check() (return x !=y;) ) Under which conditions will check () return true when called from a different class?
第1题:
若有以下程序: #include<iostream> usingnamespacestd; classA { private: int x; public: int x; void setx(int i) { x=i; } int getx() { return x; } }; class B:public A { private: int m; public: int p; void setvalue (int a,int b,int C) { setx(A) ; z=b; m=c; } void display() { cout<<getx()<<","<<z<<","<<m<<end1; } }; int main() { B obj; obj.setvalue(2,3,4); obj.display(); return 0; } 程序运行以后的输出结果是
A.产生语法错误
B.2,3,4
C.2,2,2
D.4,3,2
第2题:
有以下程序:#include <iostream>using namespace std;class A{public: A(int i,int j) { a=1; b=j; } void move (int x,int y) { a+=x; b+=y; } void show() cout<<a<<","<<b<<end1 } private: int a,b; }; class B : private A { public: B(int i,int 3):A (i,j) {} void fun() { move (3,5); } void f1() { A::show(); } }; int main() { B d(3,4); d.fun(); d.f1(); return 0; } 程序执行后的输出结果是
A.3,4
B.6,8
C.6,9
D.4,3
第3题:
有如下程序: #include<iostream> using namespace std; Class TestClass { private: int x,y; public: TestClass(int i,int j) { x=i; y=j; } void print() { cout<<“print1”<<endl; } void print()const { cout<<”prin
A.printl
B.print2
C.printl print2
D.程序编译时出错。
第4题:
若有以下程序 #include <iostream> using namespace std; class A { public: A(int i,int j) { a=i; b=j; } void move(int x, int y) { a+=x; b+=y; } void show() { cout < <a < <" , " <<b<< end1; } private: int a,b; }; class B : private A { public: B(int i,int j) :A(i,j) {} void fun ( ) { move (3, 5); } void f1 ( ) { A::show(); } }; int main ( ) { B d(3,4); d. fun ( ); d.f1(); return 0; } 程序执行后的输出结果是 ( )。
A.3,4
B.6,8
C.6,9
D.4,3
第5题:
若有以下程序: #include <iostream> using namespace std; class A { private: int x; protected: int y; public: int z; void setx(int i) { x=i; } int getx () { return x; }; class B : protected A { public: void setvalue(int a, int b, int c) { setx (a); y=b; z=c; } void display() { cout<<getx ( ) <<", "<<y<<", "<<z<<", "<<end1; } }; int main () { B obj; obj.setvalue(5, 6, 7); obj.display ( ); return 0; } 程序运行后的输出结果是( )。
A.产生语法错误
B.7,6,5
C.5,6,7
D.7,5,6
第6题:
有以下程序: #include <iostream> using namespace std; class A { public: A(int i,int j) { a=i; b=j; } void move(int x,int y) { a+=x; b+=y; } void show() { cout<<a<<","<<b<<end1; } private: int a,b; }; class B: private A { public: B(int i,int j): A(i,j) {} void fun() { move(3,5); } void fl () { A::show(); } }; int main() { B d(3,4); d.fun(); d.f1(); return 0; } 程序执行后的输出结果是
A.3,4
B.6,8
C.6,9
D.4,3
第7题:
有以下程序: #include <iostream> using namespace std; class A { private: int x,y; public: void set (int i,int j) { x=i; y=j; } int get_y() { return y; } }; class box { private: int length,width; A label; public: void set(int 1,int w, int s,int p) { length=1; width=w; label.set(s,p); } int get_area() { return length*width; } }; int main() { box small; small.set(2,4,1,35); cout<<small.get_area()<<end1; return 0; } 运行后的输出结果是( )。
A.8
B.4
C.35
D.70
第8题:
本题中,鼠标在窗口中单击一下,就在单击的位置生成一个小矩形,如果在小矩形上双击鼠标左键,则删除小矩形。 import java.awt.*; import java.awt.event.*; import javax swing.*; class MousePanel extends JPanel extends MouseMo- tionListener {public MousePanel {addMouseListener(new MouseAdapter {public void mousePressed(MouseEvent evt) {int X=evt.getX; int Y=evt.getY; current=find(x,y); if(current<0) add(x,y); } public void mouseClicked(MouseEvent evt) {int X=evt.getX; int Y=evt.getY; if(evt.getClickCount>=2) {remove(current); } } }); addMouseMotionListener(this); } public void paintComponent(Graphics g) {super.paintComponent; for(int i=0;i<nsquares;i++) draw(g,i); } public int find(int X,int y) (for(int i=0;i<nsquares;i++) if(squares[i].x-SQUARELENGTH/2<= x X<=squares[i].x+SQuARELENGTH/2 squares[i].Y-SQUARELENGTH/2< =Y y<=squares[i].Y+SQUARELENGTH /2) return i ; return-1 ; } public void draw(Graphics g,int i) {g.drawRect(squares[i].X-SQUARE- LENGTH/2。 squares[i].Y-SQUARELENGTH/2, SQUARELENGTH, SQUARELENGTH); } public void add(int X,int Y) {if(nsquares<MAXNSQUARES) {squares[nsquares]=new Point(x,y); current=nsquares ; nsquares++; repaint; } } public void remove(int n) {if(n<0 ‖ n>=nsquares)return; Nsquares- -; squares[n]=squares[nsquares]; if(current= =n)current= -l; repaint; } public void mouseMoved(MouseEvent evt) {} public void mouseDragged(MouseEvent evt) {} private static final int SQUARELENGTH=10: private static final int MAXNSQUARES=100; private Point[]squares=new Point[MAX- NSQUARES]; private int nsquares=0; private int current=-l; } class MouseFrame. extends JFramc {public MouseFrame {setTitle("java3"); setSize(300,200); addWindowListener(new WindowAdapter {public void windowClosing(WindowEvent e) {System.exit(0); } }); Container contentPane=getContentPane; contentPane.add(MousePanel); } } public class java3 {public static void main(String[]args) {JFrame. frame=new MouseFrame; frame.show; } }
第9题:
若有以下程序: #include <iostream> using namespace std; class Base { int x; protected: int y; public: int z; void setx(int i) { x=i; } int getx ( ) { return x; } }; class Inherit : private Base { private: int m; public: int p; void setvalue(int a,int b,int c, int d) { setx(a) ; y=b; z=c; m=d; } void display() { cout<<getx ()<<", "<<y<<", "<<z<<", "<<m<<end1; } }; int main() { Inherit A; A.setvalue(1,2,3,4); A.display(); return 0; } 程序运行后的输出结果是( )。
A.1,2,3,4
B.产生语法错误
C.4,3,2,1
D.2,3,4,5
第10题:
若有以下程序: #include<iostream> using namespace std; class A { private: int a; public: void seta(int x) { a=x; } void showa() { cout<<a<<","; } }; class B { private: int b; public: void setb(int x) { b=x; } void showb() { cout<<b<<",”; } }; class C:pUblic A,private B { private: int c; public: void setc(int x,int y,int z) { c=z; seta(x); setb(y); } void showc() { showa(); showb(); cout<<c<<end1; } }; int main() { Cc; c.setc(1,2,3); c.showc(); retrun 0; } 程序执行后的输出结果是
A.1,2,3
B.1,1,1
C.2,2,2
D.3,3,3