-
What is a null pointer?
There are times when it’s necessary to have a pointer that doesn’t point to anything. The macro NULL, defined in <stddef.h>, has a value that’s guaranteed to be different from any valid pointer. NULL is a literal zero, possibly cast to void* or char*. Some people, notably C++ programmers, prefer to use 0 rather than NULL. The null pointer is used in three ways: 1) To stop indirection in...
-
}
{
unsigned int bit=512;
printf("%d", bit);
}
}
">Main(){ { unsigned int bit=256; printf("%d", bit); } { unsigned int bit=512; printf("%d", bit); }}
A) 256, 512B) 512, 512C) 256, 256D) Compile errorExplanation: because these are different blocks, so declaration is allowed.
supriya ahire
- Mar 21st, 2006
hi, o/p is a)256 512 The program executes block by block.Regards,Supriya Ahire
-
-
-
What is Preprocessor?
The preprocessor is used to modify your program according to the preprocessor directives in your source code. Preprocessor directives (such as #define) give the preprocessor specific instructions on how to modify your source code. The preprocessor reads in all of your include files and the source code you are compiling and creates a preprocessed version of your source code. This preprocessed version...
-
else
printf("I hate U");
}
">Iii) main(){ float me = 1.1; double you = 1.1; if(me==you)printf("I love U");else printf("I hate U");}
I hate UExplanation:For floating point numbers (float, double, long double) the values cannot be predicted exactly. Depending on the number of bytes, the precession with of the value represented varies. Float takes 4 bytes and long double takes 10 bytes. So float stores 0.9 with less precision than long double.Rule of Thumb: Never compare or at-least be cautious when using floating point numbers with...
-
> (i - (i -1)));
}
}
">Main(){ signed int bit=512, i=5; for(;i;i--) { printf("%dn", bit >> (i - (i -1))); }}
A) 512, 512, 512, 512, 512B) 256, 256, 0, 0, 0C) 512, 256, 0, 0, 0D) 256, 256, 256, 256, 256Explanation: bit's value is not changed
-
What is the purpose of realloc( )?
the function realloc(ptr,n) uses two arguments.the first argument ptr is a pointer to a block of memory for which the size is to be altered.The second argument n specifies the new size.The size may be increased or decreased.If n is greater than the old size and if sufficient space is not available subsequent to the old region, the function realloc( ) may create a new region and all the old data are...
-
}
}
">Main(){ int i; clrscr(); for(i=0;i
A) 1, 2, 4, 8, 16B) 0, 1, 2, 4, 8C) 0, 1, 2, 3, 4D) 5, 4, 3, 2, 1Explanation: L does't make any diff.
-
}
void func2(int a[][10])
{
printf("Will this work?");
}
main()
{
int a[10][10];
func1(a);
func2(a);
}
">Void func1(int (*a)[10]){ printf("Ok it works");}void func2(int a[][10]){ printf("Will this work?");} main() { int a[10][10]; func1(a); func2(a);}
A) Ok it worksWill this work?B) Will this work?C) Ok it worksD) None of the above
visitor
- Mar 3rd, 2006
Ok it works Will this work?
-
What is use of macro arguments in c? what is major difference between normal macro definition and macro arguments.
kapil mandge
- Feb 25th, 2006
Macro is not inline function: we can see here...#SQR(x) x*xvoid inline SQR(int x){x*=x;}if we call macroSQR(++y) than it will work like this ++y*++y, value of y increamenting twice.but when we call inline function value is increamented only once i think that is right.
mef526
- Feb 13th, 2006
In above answer the macro SQR(4-y) doesn't work as expected. Can you see why?A macro is not an inline function, it is a text replacement done by the C preprocessor. Think of it as a search and replace with replaceable parameters.
-
-
# define prod(a,b)=a*bmain(){int x=2;int y=3;printf("%d",prod(x+2,y-10));}the output of the program isA. 8B. 6C. 7D. None
Rohan
- Feb 23rd, 2006
Ans is ( D ) Macro just Substitutes its arguments so ,prod ( x + 2 , y - 10 ) will be substituted by 2+2*3-10 so ans is 2+6-10=-2 None of the list given has ans is -2has ans is ( D )
-
-
-
-
-
Point out the error in the following program main() { int a=10; void f(); a=f(); printf("n%d",a); } void f() { printf("nHi"); }
The program is trying to collect the value of a "void" function into an integer variable.
-
What would be the output of the following program? main() { int y=128; const int x=y; printf("%d",x); }
A) 128B) Garbage valueC) ErrorD) 0
Amit
- Dec 12th, 2005
Correct ans is A) 128
-
}
">Main(){ int i = 100; clrscr(); printf("%d", sizeof(sizeof(i)));}
A) none of the aboveB) 4C) 100D) 2
gau_bhatnagar
- Dec 29th, 2005
Internal sizeof(i) gives output 2.2 is integer so outer sizeof()again gives output 2.
C Interview Questions
Ans