Interview FAQs : C (Answers at end of post)

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...
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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?
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3.
void main()
{
int d=5;
printf("%f",d);
}
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4.
void main()
{
int i;
for(i=1;i<4,i++) s="\12345s\n" i="1;" k=" -1"> k=255; */
signed j=-1; /* char k= -1 => k=65535 */
/* unsigned or signed int k= -1 =>k=65535 */
if(ij)
printf("greater");
else
if(i==j)
printf("equal");
}
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5.
void main()
{
char *s="\12345s\n";
printf("%d",sizeof(s));
}
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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(ij)
printf("greater");
else
if(i==j)
printf("equal");
}
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7.
void main()
{
float j;
j=1000*1000;
printf("%f",j);
}

1. 1000000
2. Overflow
3. Error
4. None
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8. How do you declare an array of N pointers to functions returning
pointers to functions returning pointers to characters?
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9.
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?
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10.
void main()
{
int i=7;
printf("%d",i++*i++);
}
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11.
#define one 0
#ifdef one
printf("one is defined ");
#ifndef one
printf("one is not defined ");
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12.
void main()
{
int count=10,*temp,sum=0;
temp=&count;
*temp=20;
temp=∑
*temp=count;
printf("%d %d %d ",count,*temp,sum);
}

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13. what is alloca()
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14.
main()
{
static i=3;
printf("%d",i--);
return i>0 ? main():0;
}
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15.
char *foo()
{
char result[100]);
strcpy(result,"anything is good");
return(result);
}
void main()
{
char *j;
j=foo()
printf("%s",j);
}
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16.
void main()
{
char *s[]={ "dharma","hewlett-packard","siemens","ibm"};
char **p;
p=s;
printf("%s",++*p);
printf("%s",*p++);
printf("%s",++*p);
}
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17. Output of the following program is
main()
{int i=0;
for(i=0;i<20;i++) c="-64;" i="-32" u ="-16;">i)
{printf("pass1,");
if(c<<2,x>>2);
}
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18. What is the ouptut in the following program
main()
{char c=-64;
int i=-32
unsigned int u =-16;
if(c>i)
{printf("pass1,");
if(c<<2,x>>2);
}
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25. Find the output for the following C program

#define swap1(a,b) a=a+b;b=a-b;a=a-b;
main()
{
int x=5,y=10;
swap1(x,y);
printf("%d %d\n",x,y);
swap2(x,y);
printf("%d %d\n",x,y);
}
int swap2(int a,int b)
{
int temp;
temp=a;
b=a;
a=temp;
return;
}
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26. Find the output for the following C program
main()
{
char *ptr = "Ramco Systems";
(*ptr)++;
printf("%s\n",ptr);
ptr++;
printf("%s\n",ptr);
}
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27. Find the output for the following C program
#include
main()
{
char *p1;
char *p2;
p1=(char *) malloc(25);
p2=(char *) malloc(25);
strcpy(p1,"Ramco");
strcpy(p2,"Systems");
strcat(p1,p2);
printf("%s",p1);
}
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28. Find the output for the following C program
# define TRUE 0
some code
while(TRUE)
{
some code
}
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29. struct list{
int x;
struct list *next;
}*head;

the struct head.x =100

Is the above assignment to pointer is correct or wrong ?
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30.What is the output of the following ?
int i;
i=1;
i=i+2*i++;
printf(%d,i);
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31. FILE *fp1,*fp2;
fp1=fopen("one","w")
fp2=fopen("one","w")
fputc('A',fp1)
fputc('B',fp2)
fclose(fp1)
fclose(fp2)
}
Find the Error, If Any?
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32. #define MAN(x,y) (x)>(y)?(x):(y)
{int i=10;
j=5;
k=0;
k=MAX(i++,++j);
printf(%d %d %d %d,i,j,k);
}
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33.void main()
{
int i=7;
printf("%d",i++*i++);
}
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34.How will u terminate the statement?
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35.select the wrong one
a.a+=1;
b.a*=2;
c.a**=1;
d.a>>=1;
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36.pick the odd one
a.malloc
b.calloc
c.new
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37.main()
{
char **p=="Hello";
printf("%s",**p);
}
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38.main()
{
printf("%d%c\n");
printf("%d%c\n");
}
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39.main()
{
int x==5;
printf("%d%d",x++,++x);
}
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40.main()
{
int x==4;
printf("%d",printf(" %d %d ",x,x) );
}
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41.main()
{
union
{
int i;
char p;
struct
{
int t;
char e;
char o;
};
};
printf("%d\n",sizeof(l) );
}
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42.main()
{
int i==0,n==6;
while(n--0);
i+==n;
printf("%d\n",i);
}
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43.a=3,b=2,c=1;
What's the value of k?
k= a< a="=" a=" 1;" i="=" i="=" a="e" s="'R';" i="=" a1="=" a2="=" t="¡;" a1="¢;" a2=" t;" s1="=" s2="s1;" temp=" s1;" a1= "new" a2= "dictionary" t="¡;" a1="¢;" a2="t;" s1=" s2;" s2=" s1;" temp=" s1;" p="=">add(dharma) && (*p)->harma)
"harma" (after printing, p->add(hewlett-packard) &&(*p)->harma)
"ewlett-packard"
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17. (d)

18. (c)

19. (b)

20. (a)

21. (b)

22. An empty string

23. 57 94

24. 5 20 1

25. 10 5

26. Samco Systems

27. RamcoSystems

28. This won't go into the loop as TRUE is defined as 0

29. Wrong

30. 4

31. no error. But It will over writes on same file.

32. 10 5 0

33. 56

34. ;

35. C

36. C

37. Garbage or nothing

38. Garbage Value

39. 6 6

40. 4 4 5

41. 4

42. -1

43. 0

44. 3

45. 16 21

46. UPPER CASE

47. 5 4 3 2 1

48. (newdictionary)-(dictionarynew)

49. (newdictionary)-(dictionarynew)

50. 50