Some important questions with answers
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
long double a=55555;
clrscr();
printf("%.2LE,%.2Le",a);
getch();
}
output:5.56E+04,5.56e+04
%e or %E represent print the number in exponential format.
%e means output has small letter e.
%E means output has capital letter e.
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
signed a=5;
unsigned b=5;
clrscr();
if(a==b)
printf("EQUAL");
else
printf("UNEQUAL");
getch();
}
output:Equal
Explanation: before any arithmetic operation small data type convert into higher data type i.e signed to unsigned.
Floating point data type questions in c programming language:
void main(){
float a=5.7e2;
clrscr();
printf("%.2f",a);
getch();
}
output:570.0
Explanation:
In 5.7e2 ,here e reperesent 10 i.e 5.7*10^2
%.2f means print only two number after decimal
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
float a=55.7E-2;
clrscr();
printf("%.2g",a);
getch();
}
output:0.56
Explanation:
In 55.7E-22 ,here E reperesent 10 i.e 55.7*10^-2
%.2f means print only two number after decimal
C best language questions and answer
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
char a='\377';
clrscr();
printf(2+"%d%o",a);
getch();
}
output:177777
Explanation:
‘\377’ is octal character constant.
%o is used to print octal number system.
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
char a='\378';
clrscr();
printf("%o",a);
getch();
}
output:error ,character constant too much long
Expalnation: Heigest possible character constant is ‘\377’ which is
Equivlalent to decimal 255.
C best programming languages questions with answer
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
char a='\12';
char *str1="cquestion",*str2="bank";
clrscr();
printf("%s%c%s",str1,a,str2);
getch();
}
output:cquestion
bank
Explanation :
‘\12’ represent octal 12 i.e. decimal 10 which is ASCII code of new line character i.e. send the cursor to next line
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
char a='\15';
char *str1="cquestion",*str2="bank";
clrscr();
printf("%s%c%s",str1,a,str2);
getch();
}
output:bankstion
Explanation :
‘\11’ represent octal 11 i.e. decimal 9 which is ASCII code of carriage return (return to first position of that line)
C best programming questions and answer
Escape sequence questions in c programming.
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
char a='\10';
char *str1="cquestion",*str2="bank";
clrscr();
printf("%s%c%s",str1,a,str2);
getch();
}
output:cquestiobank
Explanation:
‘\10’ represent octal 10 i.e. decimal 8 which is ASCII code of backspaces (only one character)
(q) What will be output of the following program?
#include"stdio.h"
void main(){
char a='\11';
char *str1="cquestion",*str2="bank";
clrscr();
printf("%d",printf("%s%c%s",str1,a,str2));
getch();
}
output: cquestion bank14
Explanation :
‘\11’ represent octal 11 i.e. decimal 9 which is ASCII code of blank space.
C best questions with answer
(q) What will be output of the following program?
#include"stdio.h"
void main(){
char a='\7',b='\8';
clrscr();
printf("%d %d",a,b);
getch();
}
output:7 56
Expalnation:
8 is not octal digit. octal digits are(0,1,2,3,4,5,6,7).
So ‘\7’ is octal 7
‘\8’ some special character constant.
C coding good questions and answer
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
char a='\\';
clrscr();
a=a-'/';
printf("%d",a);
getch();
}
output:error
Explanation:
Character is \ has special meaning in c programming.
e.g
‘\0’ represent octal character.
‘\n’ represent new line character. So we cannot use ‘\’ directly.
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
char a='\5';
clrscr();
a=a<<2;
printf("%x",a);
getch();
}
output:14
C language good questions with answer
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
//clrscr();
fputs("STANDARD PRINTER DEVICE",stdprn);
getch();
}
output: STANDARD PRINTER DEVICE (on the paper)
Explanation:
PRINT IN CONNECTED PRINTER DEVICE, OTHERWISE
TURBO C WILL BE HANGED FOR SEARCHING OF PRINTER IN THE SYSTEM.
Character constant questions in c programming language.
(q) What will be output of the following program?
#include"stdio.h"
void main(){
char a='\';
clrscr();
printf("%c",a);
getch();
}
output: error,unterminated character constant
Explanation:
Character is \ has special meaning in c programming.
e.g
‘\0’ represent octal character.
‘\n’ represent new line character. So we cannot use ‘\’ directly.
C programming good languages questions and answer
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
clrscr();
fputs("STANDARD OUTPUT PAGE",stdout);
getch();
}
output: STANDARD OUTPUT PAGE
it will display the output of program on standard output page or stream(by default for text)
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
clrscr();
fputs("STANDARD INPUT PAGE",stdin);
getch();
}
output: nothing
stdin is used as standard input device stream.
C programming good questions with answer
Standard predefined stream question in c programming language.
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
clrscr();
fputs("ERROR page",stderr);
getch();
}
output: ERROR PAGE
explanation:
it will display the output of program on standard error page
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
clrscr();
fputs("STANDARD AUXILIARY PAGE",stdaux);
getch();
}
output: It will show a system message :
BAB MEMORY IMAGE OF FAT DETECTED
Note: stdaux is standard auxiliary device in c.
C good questions and answer
(q) What will be output of the following program ?
void main(){
enum data1{a,c,e}p;
enum data2{b,d,f}q;
p=q;
clrscr();
printf("%i",p);
getch();
}
output: 0
Standard predefined stream question in c programming language.
(q) What will be output of the following program ?
#include"stdio.h"
void main(){
clrscr();
fputs("ERROR page",stderr);
getch();
}
output: ERROR PAGE
explanation:
it will display the output of program on standard error page
best questions of c coding and answer
(q) What will be output of the following program ?
void main(){
enum data{a=5,b=a,c=a+b,d=+a+b+c};
clrscr();
printf("%#o",d);
getch();
}
output: 024
Explanations:
We can initialize enum constant with other enum constant.
(q) What will be output of the following program ?
void main(){
enum {a=5,b=a,c=a^b,d=a^b^c};
clrscr();
printf(2+"p=%#o",d);
getch();
}
output: 0
Explanations:
We can initialize enum constant with other enum constant and perform arithmetic ,logical operation etc.
^ is bitwise XOR operator.
%o is used for octal number.
best questions of c language and answer
(q) What will be output of the following program ?
void main(){
enum data{a,b=-1,c};
clrscr();
printf("%i %i %i",c,c++,++c);
getch();
}
output: error lvalue required
Explanation:
You cannot modify enum constant after initialization.
(q) What will be output of the following program ?
void main(){
enum data{a,b=-1,c=300000,d=0,e};
clrscr();
printf("%#x",c);
getch();
}
output: error
value of enum constant must be within the range of signed int.
best questions of c programming and answer
enum data type questions in c programming language.
(q) What will be output of the following program ?
void main(){
enum data{a,b,c};
clrscr();
printf("%i %i %i",a,b,c);
getch();
}
output: 0 1 2
Explanation:
By default initial value of first enum constant is zero.
Value of next enum constant will be :
Next_enum_constant_value= previous_enum_constant_value+1
(q) What will be output of the following program ?
void main(){
enum data{a,b=5,c};
clrscr();
printf("%i %i %i",a,b,c);
getch();
}
Output: 0 5 6
Explanation:
By default initial value of first enum constant is zero.
Value of next enum constant will be:
Next_enum_constant_value= previous_enum_constant_value+1
This formal is valid if enum constant is not explicitly initialized.
Otherwise it will store initialized value.
best questions of c with answer
void main(){
int x=012,y;
clrscr();
y=++x- ~x+4?5:6;
printf("%#X %x",y,y);
getch();
}
Output: 0X5 5
Explanation:
012 is octal number because it is staring with number zero.
%x,%X is used for to print the number in hexadecimal format.
# indicates output should in the format: 0x number.
(q) What will be output of the following program ?
void main(){
int x=0x12,y;
clrscr();
y=(x,1,10)+x,1,10;
printf("%#o, %o",y,y);
getch();
}
output: 034 34
Explanation:
0x12 is hexadecimal number because it is staring with 0x.
%o is used for to print the number in octal format.
# indicates output should in the format: 0 numbers.
good questions of c coding with answer
number system like octal, hexadecimal in questions c programming language.
(q) What will be output of the following program ?
void main(){
int x=0x25,y;
clrscr();
y=++x -x+printf("x");
printf("\n%d",y);
getch();
}
output: x
1
Explanation:
Ox represents hexadecimal number system.
Note. Printf function returns an integer which is number of character.
(q) What will be output of the following program?
void main(){
int x=12,y;
clrscr();
y=++x <
printf("%#X",y);
getch();
}
output: 0xA000
Explanation:
%x,%X is used for to print the number in hexadecimal format.
# indicate output should in the format 0x number
good questions of C programming languages and answer
(q) What will be output of the following program ?
void main(){
clrscr();
printf("%d",__LINE__);
getch();
}
output: 3
Explanation:
__LINE__ is global identifier in c programming language. It return an integer which is equal to total number of line in c source code program
upto __LINE__ including that line.
e.g
void main(){ //line 1
clrscr(); //line 2
printf("%d",__LINE__); //line 3
(q) What will be output of the following program ?
//save this program as test.c
void main(){
clrscr();
printf("%s",__FILE__);
getch();
}
output: test.c
Expalnation:
__FILE__ is global identifier in c programming language. It returns
a string containing name of current source file in which this program
has been saved.
good questions of c programming with answer
Global identifier questions c programming language.
(q) What will be output of the following program ?
void main()
{
clrscr();
printf("%s",__TIME__);
getch();
}
output: 22:45:19
Explanation:
__TIME__ is global indetifer in c. It will display current time (h:m:s)of system in which you are working.
(q) What will be output of the following program ?
void main()
{
clrscr();
printf("%s",__DATE__);
getch();
}
output: sept 12 2008
_TIME__ is global identifier in c. It will display current date (month date year)of system in which you are working
good questions of c with answer
volatile modifier keyword questions in c programming language:
(q) What will be output of the following program ?
void main()
{
volatile a=5;
a=~a+ ++a;
clrscr();
printf("%d",a);
getch();
}
output: -1
Explanation:
volatile variable can be modify by interrupt or other process in preprocessor. So in normal output will not affect.
Note. ~ is one’s complement operator
(q) What will be output of the following program ?
void main()
{
volatile a=5;
a=~a+++a;
clrscr();
printf("%d",a);
getch();
}
output: 0
Explanation:
volatile variable can be modify by interrupt or other process in preprocessor. So in normal output will not affect.
a+++a means a++ + a.
Note. ~ is one’s complement operator.
questions of c coding and answer
(q) What will be output of the following program ?
void main()
{
int * const a=(int * const)12;
a=25;
clrscr();
printf("%d",a);
getch();
}
output: error
Explanation:
we Cannot modify a const object.
Here address of a is not constant but variable a is constant. So we
Cannot modify variable a.
questions of c language with answer
(q) What will be output of the following program ?
void main()
{
const int *a=12;
a++;
clrscr();
printf("%d",a);
getch();
}
output: garbage value
Explanation: Here address of variable a is constant not variable a. So we can modify variable a. Initial value of auto type data is garbage.
(q) What will be output of the following program ?
void main()
{
const int *a=(const int * )12;
*a=(const int *)25;
clrscr();
printf("%d",a);
getch();
}
output: error
Explanation:
we Cannot modify a const object.
Here address of a is constant not variable a.
questions of C programming languages and answer
const modifier keyword questions in c programming language:
(q) What will be output of the following program ?
void main()
{
const a=10;
a=~a;
printf("%d",a);
getch();
}
output: error
Explanation:
we Cannot modify a const object.
(q) What will be output of the following program ?
void main()
{
const _=10;
int *p=&_;
printf("%d",*p);
getch();
}
output: 10
Explanation:
We can assign address of const object to its pointer.
underscore is valid variable name.
questions of c programming with answer
(q) What will be output of the following program ?
void main()
{
int x=5;
int y=10;
&x=y;
printf("%d %d",x,y);
getch();
}
output: error ,L value required
Explanation:
After applying any operator in variable name it always give a value.
(type): urinary type casting operator is not exception for this.
It is similar to write
3456=5
It is invalid c statement. Because left side of assignment operator must be a variable not any constant.
questions of c and answer
(q) What will be output of the following program ?
void main()
{
long int a,b=5;;
~a=++b + ++b + ++b;
printf("%d %d",++a,++b);
getch();
}
output: error ,L value required
Explanation:
After applying any operator in variable name it always give a value.
(type): urinary type casting operator is not exception for this.
It is similar to write
3456=5
It is invalid c statement. Because left side of assignment operator must be a variable not any constant.
(q) What will be output of the following program ?
void main()
{
int x;
int y;
x+y=10;
x=3;
printf("%d",y);
getch();
}
output: error ,L value required
Explanation:
After applying any operator in variable name it always give a value.
(type): urinary type casting operator is not exception for this.
It is similar to write
3456=5
It is invalid c statement. Because left side of assignment operator must be a variable not any constant.
C coding questions with answer
L value required error in c programming language:
(q) What will be output of the following program ?
void main()
{
long int a;
(float)a=6.5;
printf("%f",a);
getch();
}
output: error ,L value required
Explanation:
After applying any operator in variable name it always give a value.
(type): urinary type casting operator is not exception for this.
It is similar to write
3456=5
It is invalid c statement. Because left side of assignment operator must
Be a variable not any constant.
(q) What will be output of the following program ?
void main()
{
long int a,b=10;
++a=b++;
printf("%d %d",a,b);
getch();
}
output: error ,L value required
Explanation:
After applying any operator in variable name it always give a value.
(type): urinary type casting operator is not exception for this.
It is similar to write
3456=5
It is invalid c statement. Because left side of assignment operator must
Be a variable not any constant.
C language questions and answer
(q) What will be output of the following program ?
void main(){
char * __TIME__="world";
clrscr();
printf("%s ",__TIME__);
getch();
}
output:error
Explanation:
__TIME__ is valid identifier in c programming language but it is
Predefine global identifier .So a variable not should not be global
Identifier like __TIME__,__DATE___,__FILE__ etc.
C programming languages questions with answer
(q) What will be output of the following program ?
void main()
{
long int _=5l;
printf("%ld",_);
getch();
}
output: 5
Explanation:
Under score is valid keyword in c.
(q) What will be output of the following program ?
void main(){
char * __WORLD__="world";
clrscr();
printf("%s ",__WORLD__);
getch();
}
Output:world
Explanation:
__WORLD__ is valid identifier in c programming language.
But we should not write variable name in the forma like __xyx__,
__TIME__. Why ?
C programming questions and answer
(q) What will be output of the following program ?
void main()
{
Char * emp name=”raja”;
printf("%s",emp name);
getch();
}
output:error
Explanation:
invalid variable name.Except under score there should not be any special character in name of variable event blank space.
(q) What will be output of the following program ?
void main()
{
long int new=5l;
printf("%ld",new);
getch();
}
output:5
Explanation:
We can use c++ keyword in variable name in c programming.(But should not use ,why ?)
C questions with answer
Variable naming rule in c programming language:
(q) What will be output of the following program ?
void main()
{
int goto=5;
printf("%d",goto);
getch()
}
Output:error
Explanation:
invalid variable name. goto is keyword in c.
(q) What will be output of the following program ?
void main()
{
long int 1a=5l;
printf("%ld",1a);
getch();
}
Output:error
Explanation:
invalid variable name. Variable name must star from either alphabet or
under score.
solution of your query
Welcome to ask query
(q)
date 9/4/08
Hi!
I hope u will be fine.plz help in following program.I need source code.
The question is:
A string (eg: "I am writing an email") is entered through the keyboard, write a programme in C to get its reverse in a column as output ie:
email
an
writing
am
Answer:
code for such program is:
void main()
{
char str[20];
char *ptr=str,*temp;
int i=0,j;
clrscr();
scanf("%[^\n]",str);
while(*ptr){
i++;
ptr++;
}
for(j=0;j
if(*ptr==' ')
{
temp=ptr;ptr--;temp++;
while((*temp!=' ')&&(*temp!='\0')) {
printf("%c",*temp);
temp++;
}
printf("\n");
}
else
{
ptr--;
}
}
while(*ptr!=' ') {
printf("%c",*ptr);
ptr++;
}
getch();
}
(q)
I want a C program to check whether a string is a palindrome or not where the string to be checked is passed as command line argument during execution.
(pahal ray
8/25/08
Answer:
#include"string.h"
void main(int counter,char**string)
{
char *rev;
char str[15];
int i,j;
clrscr();
strcpy(str,string[1]);
printf("%s",str);
for(i=strlen(str)-1,j=0;i>=0;i--,j++)
rev[j]=str[i];
rev[j]='\0';
if(strcmp(rev,str))
printf("\nThe string is not a palindrome");
else
printf("\nThe string is apalindrome");
getch();
}
(q)
how to write a c program to display the source code of the program.
(ramya)
8/23/08
answer:
If source code is available
#include"stdio.h"
void main()
{
char str[70];
FILE *p;
clrscr();
if((p=fopen("mod.c","r"))==NULL)
{
printf("\nUnable t open file string.txt");
exit(1);
}
while(fgets(str,70,p)!=NULL)
puts(str);
fclose(p);
getch();
}
(q) Swapping of two number without using third variable
answer
void main()
{
int a=5,b=10;
clrscr();
//process one
a=b+a;
b=a-b;
a=a-b;
printf("a= %d b= %d",a,b);
//process two
a=5;b=10;
a=a+b-(b=a);
printf("\na= %d b= %d",a,b);
//process three
a=5;b=10;
a=a^b;
b=a^b;
a=b^a;
printf("\na= %d b= %d",a,b);
//process four
a=5;b=10;
a=b-~a-1;
b=a+~b+1;
a=a+~b+1;
printf("\na= %d b= %d",a,b);
//process five
a=5,b=10;
a=b+a,b=a-b,a=a-b;
printf("\na= %d b= %d",a,b);
getch();
}
(q) How to convert Decimal to binary in c programme?
answer
void main()
{
long int m,no=0,a=1;
int n,rem;
clrscr();
printf("Enter any decimal number->");
scanf("%d",&n);
m=n;
while(n!=0)
{
rem=n%2;
no=no+rem*a;
n=n/2;
a=a*10;
}
printf("The value %ld in binary is->",m);
printf("%ld",no);
getch();
}
