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Write a program to get the following output ..n should be entered by user...like when n=5 the output should be110101101010101
sivaraju.sateesh
- Jul 20th, 2010
#include<stdio.h>main(){int n,i=4,j;scanf("%d",&n);while(i<=n+3){for(j=3;j<i;j++){printf("%d",j%2);}printf("n");i++;}}
R.S.Jayasathyanarayanan
- Dec 17th, 2006
void main(){ int i,n; ...
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Compare Two Files in C
Write a program that compares two files and return 0 if they are equal and 1 if they are not equal.
yongpark210
- Jul 15th, 2010
#include <iostream>using namespace std;int CmpFiles(void);int _tmain(int argc, _TCHAR* argv[]) {CmpFiles();return 0; }int CmpFiles(void) {int cmp = 0; FILE *pF1, *pF2;char c1[16], c2[16]; pF1 = ...
iantuy
- Apr 26th, 2009
int main(int argc, char* argv[]) { if(argc!=3) return -1; FILE *fp1, *fp2; fp1 = fopen(argv[1],"r"); fp2 = fopen(argv[2],"r"); if(!fp1 || !fp2) return...
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Efficient Sorting Method
If we add a element to the last of a sorted sequence. Then which of the sorting method will be most efficient to sort the new sequence?
netsim
- Jul 9th, 2010
It depends on the date struct to store the sequence.The answer for array or linked list will be different.
akhil kumar jha
- Feb 28th, 2010
I think radix sorting would be more perfect in case of large sequence of elements as because it will reduce the no. of elements to be compared to a minimal. As it goes on to check the inserted el...
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}">
What is the output of the following program?void main(){int *ptr =55;clrscr();printf("%d", ++(ptr));}
jbode
- Jul 6th, 2010
The result is undefined (meaning the output could be just about anything, including no output at all) for several reasons, the most pertinent one being that the "%d" conversion specifier exp...
kbjarnason
- Jul 2nd, 2010
First, the program won't even compile, as C has no clrscr function and you haven't provided one.Second, if you fix that, the program still relies upon undefined behaviour - void main has never...
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return a;
}
int main()
{
char *b;
b = f();
printf("%s",b);
}
Is there any error in this code?">Char *f(void){ char *a; a=malloc(sizeof(char)*10); strcpy(a,"hello World"); return a; }int main(){ char *b; b = f(); printf("%s",b); }Is there any error in this code?
jbode
- Jul 6th, 2010
@vipin gupta: Another point to note that the function malloc will return a void pointer which should be explicitly typecasted into char *. Althouth this wouldn't generate any error (only a warning) bu...
kbjarnason
- Jul 2nd, 2010
First error: no prototype for malloc in scope, meaning that the compiler will think malloc returns an int, not a pointer, which on some systems will dramatically pooch your code as soon as you do the ...
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Field Width Specification
What is Field Width Specification?
jbode
- Jul 6th, 2010
I'm assuming this is the minimum field width in a conversion specification for printf(), which specifies the minimum number of characters written to the output stream for that conversion. For ex...
kbjarnason
- Jul 1st, 2010
Presumably the question is about the width specifier on bit-fields:int x : 7;In this case, the width specifier (7 in our example) tells the compiler that the bit-field (x) will use 7 bits, rather than...
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How can you get the number of elements in an array allocated dynamically at runtime? For example -int *p = (int *) malloc(sizeof(int) * n);int numElems = ??????? /* n is not available here */
jbode
- Jul 6th, 2010
If all you have is the pointer p, then there is no (standard) way to determine how many elements were allocated to the chunk it's pointing to. If you have to keep track of how big your dynamic b...
kbjarnason
- Jul 2nd, 2010
The short answer is, you can't.With static arrays, you know the size of both the array and its elements and can simply work it out. With dynamically allocated arrays, the size information is...
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What will be difference b/w 5th and 6th statements?
1. #define MAX 1002. main()3. {4. int max=100;5. int a[MAX];6. int b[max];7. }
jbode
- Jul 6th, 2010
Line 6 defines a variable-length array, which is only valid for C99 or later. The size of a VLA is not known until runtime, they may not declared static or extern, and only ordinary identifiers ...
kbjarnason
- Jul 1st, 2010
In C99, the differences are that b is defined, rather than a, and that b is a variable-length-array rather than a conventional array.In C90, the sixth line is an error, as C90 does not support VLAs.
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Fflush() in Multiple Scanf calls
What is the requirment of using fflush() in multiple scanf calls.
jbode
- Jul 6th, 2010
The behavior of fflush() is not defined for input streams. If you need to clear extraneous or garbage data from an input stream, you'll have to use some other method. When dealing with...
kbjarnason
- Jul 1st, 2010
There is no requirement to use fflush in multiple scanf calls. fflush operates exclusively on output streams, thus has no relation to scanf, which is an input function.That said, if one is using...
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strcat(buf,buf);
printf(buf);
}
While executing this in VC++ I do not get an output . Looks like the program runs into an infinite loop. But while executing the same in Turbo C I get the output as "hellohelloh". What could be the reason behind this difference in output?">Consider the following program segment :#include #include void main () { char buf[100] = "hello"; strcat(buf,buf); printf(buf);}While executing this in VC++ I do not get an output . Looks like the program runs into an infinite loop. But while executing the same in Turbo C I get the output as "hellohelloh". What could be the reason behind this difference in output?
jbode
- Jul 6th, 2010
As kbjarneson pointed out, the problem is that you are clobbering the 0 terminator of the input string; once that happens, strcat() doesn't know where to stop. His solution is to use memmove...
kbjarnason
- Jul 2nd, 2010
Consider how strcat might be written:strcat( char *dst, char *src ){ /* Find end of string */ while ( *dst ) dst++; while ...
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What is the difference between text and binary modes?
Streams can be classified into two types: text streams and binary streams. Text streams are interpreted, with a maximum length of 255 characters. With text streams, carriage return/line feed combinations are translated to the newline n character and vice versa. Binary streams are uninterpreted and are treated one byte at a time with no translation of characters. Typically, a text stream would be used...
kbjarnason
- Jul 2nd, 2010
The primary differentiation between text and binary modes as far as C is concerned has to do with line endings.? Take a look at a printf statement; note that many of them end in a n.? n is not, as one...
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How many times fork() function is executed
Main(){ if(fork()||fork()) return fork(); else return 0;}how many times fork() function is executed?
geekeeg
- Jun 30th, 2010
4 times.Main threadfork() fork() /* In Child process second fork call */ &n...
suhaas.kaul
- Feb 4th, 2009
fork f1 = 1 will return f3;fork f1 = 0, f2 = 1 return f3;f1 = 0, f2 = 0 return 0;in all 7 times;
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Why n++ executes faster than n+1?
The expression n++ requires a single machine instruction such as INR to carry out the increment operation whereas, n+1 requires more instructions to carry out this operation.
kbjarnason
- Jul 2nd, 2010
If n++ executes faster than n = n + 1, the reason for it is simple: your compiler has a poor optimizer.
romainn
- Jun 14th, 2007
N++ takes more than one instruction, ++n is faster. n++ has to store n, increment the variable and return n, while ++n increment n and return without storing the previous value of n.
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Between a long pointer and a char pointer , which one consumes more memory? explain
kbjarnason
- Jul 2nd, 2010
As a general rule of thumb, object pointers (as opposed to function pointers) will typically be the same size, as the relevant information - memory address - requires the same size regardless of type....
abhimanipal
- Jul 20th, 2009
I am sorry the 2 part of the above answer is wrong..... I confused long pointer with far pointerSIze of long pointer and char pointer will be the same
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What do you mean by normalisation of pointers
kbjarnason
- Jul 2nd, 2010
Generally, this term applies only in ancient DOS-based compilers when using far or huge pointers.In 16-bit DOS compilers, the default ("near mode/small mode") is to have all the data in one ...
Ahtesham Ali
- Jun 20th, 2006
Normalization functions are provided which take any of these combined types as their first argument, a pointer to the same combined type as their second argument, and place the normalization of the first into the second.
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If we pass null pointer in malloc or calloc function, What will be the result?
kbjarnason
- Jul 2nd, 2010
You don't pass null pointers to malloc or calloc. You can pass them to realloc.Perhaps you mean what would happen if you did this:#include <stdlib.h>int main(void){ char *p...
kannan987
- Jun 13th, 2008
Test.h is nothing but in my pgm..simply include all header files..<----test.h--->#include<stdio.h>#include<conio.h>#include<stdlib.h>#include<string.h>
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What is a sequence point? what is its significance?
kbjarnason
- Jul 2nd, 2010
A sequence point is a point in the flow of the program at which certain things have to be completed before the code can continue.For example, suppose you had the following in your code: pr...
ganesh.g
- Sep 5th, 2007
A sequence point is loosely referred as the point at which an expression is evaluated and all the objects involved in that expression are assigned their fresh values, if any.Example: 1. Between the st...
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What is the difference between the functions rand(), random(), srand() and randomize()?
kbjarnason
- Jul 2nd, 2010
The first difference is that random and randomize are not part of the standard C language, so we'll ignore them.rand() produces a (pseudo) random integer in the range 0 to RAND_MAX. There ar...
sanjeev
- Sep 25th, 2007
RAND: Rand uses a multiplicative congruential random number generator with period232 to return successive pseudo-random numbers in the range 0 to RAND_MAX. Return Value: Rand returns the generated...
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Why scanf("%d",&n) and gets(string) don't work together?
kbjarnason
- Jul 2nd, 2010
The solution is *NOT*, as another writer posted, to use fflush(stdin), because fflush is defined only for *output* streams, and stdin is not an output stream. Yes, your implementation may suppor...
baseersd
- Sep 18th, 2007
This is a general problem of the keyboard buffer. When scanf("%d",&n); is used and when an input is entered, the newline character("n") along with the input is stored in buffer...
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What does type qualifier volatile indicate to the compiler?
kbjarnason
- Jul 2nd, 2010
An optimizing compiler can examine the flow of code and (in many cases) determine whether a variable is actually modified or not; if not, then there's no reason to read the value from memory more ...
hemanth
- Sep 25th, 2007
Indicate that a variable can be changed by a background routine.
C Interview Questions
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