C,C++ Quiz

1. Base class has some virtual method and derived class has a method with the same name. If we initialize the base class pointer with derived object,. calling of that virtual method will result in which method being called?
a. Base method 
b. Derived method..

Ans: b

2. For the following C program 
#define AREA(x)(3.14*x*x)
main()
{

        float r1=6.25,r2=2.5,a;
        a=AREA(r1);
        printf("\n Area of the circle is %f", a);
        a=AREA(r2);
        printf("\n Area of the circle is %f", a);
}

What is the output? 

Ans:

Area of the circle is 122.656250

Area of the circle is 19.625000

3.void main()  {
       int d=5;
       printf("%f",d);
  }

Ans: Undefined

4.void main()
{
     int i;
     for(i=1;i<4,i++)
     switch(i)
             case 1: printf("%d",i);break;
             {
             case 2:printf("%d",i);break;
             case 3:printf("%d",i);break;
             }
             switch(i) 

                      case 4:printf("%d",i);
}

Ans: 1,2,3,4

5.void main()  {
          char *s="\12345s\n";
          printf("%d",sizeof(s));
  }

Ans: 6

6.void main()  {
           unsigned i=1; /* unsigned char k= -1 => k=255; */
           signed j=-1; /* char k= -1 => k=65535 */
           /* unsigned or signed int k= -1 =>k=65535 */
           if(i<j)
                  printf("less");
           else
                  if(i>j)
                          printf("greater");
                  else
                          if(i==j)
                          printf("equal");
  }

Ans: less

7.void main()   {
          float j;
          j=1000*1000;
          printf("%f",j);
   }

1. 1000000
2. Overflow
3. Error
4. None 

Ans: 4

8.int f()  void main()
  {
       f(1);
       f(1,2);
       f(1,2,3);
  }
  f(int i,int j,int k)
  {
       printf("%d %d %d",i,j,k);
  }
What are the number of syntax errors in the above?

Ans: None.

9.void main() 

  {
        int i=7;
        printf("%d",i++*i++);
  }

Ans: 56

10.#define one 0 

    #ifdef one
    printf("one is defined ");
    #ifndef one
     printf("one is not defined ");

Ans: "one is defined"

11.void main() 

    {
           int count=10,*temp,sum=0;
           temp=&count;
           *temp=20;
           temp=&sum;
           *temp=count;
           printf("%d %d %d ",count,*temp,sum);
   }

Ans: 20 20 20

12.what is alloca()

Ans : It allocates and frees memory after use/after getting out of scope

13.main() 

    {
         static i=3;
         printf("%d",i--);
         return i>0 ? main():0;
    }

Ans: 321

14.char *foo() 

    {
         char result[100]);
         strcpy(result,"anything is good");
         return(result);
    }
    void main()
    {
         char *j;
         j=foo()
         printf("%s",j);
    }

Ans: anything is good.