Line 26 prints “a” to System.out.
Line 26 prints „b” to System.out.
An exception is thrown at line 26 at runtime.
Compilation of class A will fail due to an error in line 6.
第1题:
有如下类声明: class XA { int x; public: XA(int n){x=n;} }; class XB:public XA { int y; public: XB(int a,int b); }; 在构造函数XB的下列定义中,正确的是
A.XB::XB(int a,int b):x(a),y(b){}
B.XB::XB(int a,int b):XA(a),y(b){}
C.XB::XB(int a,int b):x(a),XB(b){}
D.XB::XB(int a,int b):XA(a),XB(b){}
第2题:
下面程序段的输出结果为( )。 package test; public class ClassA { int x=20: static int y=6; public static void main(String args[]) { ClassB b=new ClassB; go(10); System.out.println("x="+b.x); } } class ClassB { int X; void go(int y) { ClassA a=new ClassA; x=a.Y ; } }
A.x=10
B.x=20
C.x=6
D.编译不通过
第3题:
执行下面程序段,屏幕上将输出( )。 public class Test { private int x=10,y=20; public Test (int x,int y) { System.out.println (x+this.x); System.out.println (y+y); } public static void main (String[] args) { Testt= new Test(30,50); } }
A.无输出
B.20 40
C.40 100
D.40 70
第4题:
下列代码执行之后,输出的结果为______。 public class ex38 { public static void main(String[] args) { int x=12; int m=11; int y=13; int temp=x>y?x:y; temp=temp>m?temp:m; System.out.println (temp); } }
A.1
B.12
C.13
D.11
第5题:
下面程序段的输出结果为 package test; public class A { int x=20; static int y=6; public static void main(String args[]) { Class B b=new Class B(); b.go(10); System.out.println(”x=”+b.x); } } class Class B { int x; void go(int y) { ClassA a=new ClassA(); x=a.y; } }
A.x=10
B.x=20
C.x=6
D.编译不通过
第6题:
执行下面程序,显示的结果为( )。 public class Test { public static void main (String args[]) { Test t=newTest(); System.out.println (Loverload ("2","3")); } int overload (intx,int y) {return x+y;} String overload (String x,Stnng y){return x+y;} }
A.2
B.3
C.5
D.23
第7题:
有如下程序: #include <iostream.h> class x { protected: int a; public: x() { a=1; } }; class x1 : virtual public x { public: x1() { a+=1; cout<<a; } }; class x2 : virtual public x { public: x2() { a+=2; cout<<a; } }; class y : public xl,public x2 { public: y() { cout<<a<<end1; } }; int main() { y obj; return O; } 该程序运行后的输出结果是( )。
A.1
B.123
C.242
D.244
第8题:
下列程序运行后的输出结果是( )。#include#includeusing namespace std;class Person{public:Person(string n):name(n) { cout<<'P'; }private:string name;};class Date{public:Date(int y=2012,int m=12,int d=21):year(y),month(m),day(d) { cout<<'D'; }
private:int year,month,day;};class Student:public Person{public:Student(string n,int y,int m,int d,char c):birthday(y,m,d),sex(c),Person(n) { cout<<'S'; }private:Date birthday;char sex;};int main(){Student stu1("Zhang",1990,10,1,'F');return 0}
A. S
B.PS
C.DPS
D.PDS
第9题:
下面程序输出的结果是( )。 #include<iostream> using namespace std; class A{ int X; public: A(int x):x(++x){} ~A(){cout<<x;} }; class B:public A{ int y; public: B(int y):A(y),y(y){} ~B(){cout<<y;}; }; void main(){ B b(3); }
A.34
B.43
C.33
D.44
第10题:
下列程序的输出结果是______。
include<iostream.h>
class base
{
int x,y;
public:
base(int i,int j){x=i;y=j;}
virtual int add( ){return x+y;}
};
class three:public base
{
int z;
public:
three(int i,int j,int k):base(i,j){z=k;)
int add( ){return(base::add( )+z);}
};
void main( )
{
three*q=new three(10,20,30);
cout<<q->add( )<<endl;
}