Basic Programs | Student Projects

How to count set bits in a number

Chitra — Tue, 12 Apr 2022 14:10:24 +0000

First version:

  int CoutSetBits(int Num) {

  for (int count = 0; Num; Num >>= 1) {
    if (Num & 1)
      count++;
  }
  return count;
}

Optimized version:

  int CoutSetBits(int Num) {

  for (int count = 0; Num; count++) {
    Num &= Num - 1;
  }
}

The post How to count set bits in a number first appeared on Student Projects.

How to write a function that finds the last instance of a character in a string

Chitra — Tue, 12 Apr 2022 14:06:02 +0000

char * lastchar(char * String, char ch) {
  char * pStr = NULL;

  // traverse the entire string

  while ( * String++ != NULL) {
    if ( * String == ch)
      pStr = String;
  }

  return pStr;
}

The post How to write a function that finds the last instance of a character in a string first appeared on Student Projects.

How to generate a Fib numbers

Chitra — Tue, 12 Apr 2022 14:04:49 +0000

int fib( n ) // recursive version
{
	
	if ( n < 2 )
		return 1;
	else
		return fib ( n –1 ) + fib ( n –2 );

}

int fib( n ) //iterative version
{
	int f1 =1, f2 = 1;

	if ( n < 2 )
		return 1;	
	for ( i = 1; i < N; i++)
	{
		f = f1 + f2;
		f1= f2;
		f = f1;
	}

	return f;
}

The post How to generate a Fib numbers first appeared on Student Projects.

How to find the factorial of a number

Chitra — Tue, 12 Apr 2022 14:03:50 +0000

//
// recursive version
//

int Factorial(int Num) {

  If(num > 0)
  return Num * Factorial(Num– 1);
  else
    return 1;
}

//
// iterative version
//

int Factorial(int Num) {
  int I
  int result = 1;

  for (I = Num; I > 0; I--) {
    result = result * I;
  }

  return result;
}

The post How to find the factorial of a number first appeared on Student Projects.

How to print an integer using only putchar

Chitra — Tue, 12 Apr 2022 13:48:51 +0000

//
//	recursive version
//
void PrintNum(int Num) {
  if (Num == 0)
    return;
  PrintNum(Num / 10);
  Puthcar(‘0’ + Num % 10);
}

The post How to print an integer using only putchar first appeared on Student Projects.

How to write a function that takes in a string parameter and checks to see whether or not it is an integer, and if it is then return the integer value

Chitra — Tue, 12 Apr 2022 13:45:49 +0000

#include 

int strtoint(char * s) {
  int index = 0, flag = 0;

  while ( * (s + index) != '\0') {
    if (( * (s + index) >= '0') &&
      *
      (s + index) <= '9') {
      flag = 1;
      index++;
    } else {
      flag = 0;
      break;
    }
  }

  if (flag == 1)
    return atoi(s);
  else
    return 0;
}

main() {
  printf("%d", strtoint("0123"));
  printf("\n%d", strtoint("0123ii"));
}

The post How to write a function that takes in a string parameter and checks to see whether or not it is an integer, and if it is then return the integer value first appeared on Student Projects.

How to convert a string to the upper case

Chitra — Tue, 12 Apr 2022 05:17:50 +0000

void ToUpper(char * S) {
  while ( * S != 0) {
    * S = ( * S >= 'a' && * S <= 'z') ? ( * S - 'a' + 'A') : * S;
    S++;
  }
}

The post How to convert a string to the upper case first appeared on Student Projects.

How to reverse a string

Chitra — Tue, 12 Apr 2022 05:06:59 +0000

void ReverseString(char * String) {
  char * Begin = String;
  char * End = String + strlen(String) - 1;
  char TempChar = '\0';

  while (Begin < End) {
    TempChar = * Begin;
    * Begin = * End;
    * End = TempChar;
    Begin++;
    End--;
  }
}

The post How to reverse a string first appeared on Student Projects.

Find the output of the cpp program

Arun — Thu, 29 Nov 2012 10:57:02 +0000

What is the output of below code?

#include "iostream"
using namespace std;
int main()
{
    int i;
    i = 1 + ( 1, 4, 5, 6, 3);
    cout<
a) 4

b) 7

c) compile time error

d) no output
The correct answer for this question is b)7 if we perform the arithmetic operation with in parenthesis the largest number from the set is taken for computation of output
The post Find the output of the cpp program first appeared on Student Projects.

C++ program to implement Heap sort Algorithm

Editorial Team — Tue, 01 Feb 2011 13:38:53 +0000

#include 
const int MAX = 10 ;
class array
{
	private :
		int arr[MAX] ;
		int count ;
	public :
		array( ) ;
		void add ( int num ) ;
		void makeheap(int ) ;
		void heapsort( ) ;
		void display( ) ;
} ;
array :: array( )
{
	count = 0 ;
	for ( int i = 0 ; i < MAX ; i++ )
		arr[MAX] = 0 ;
}
void array :: add ( int num )
{
	if ( count < MAX )
	{
		arr[count] = num ;
		count++ ;
	}
	else
		cout << "\nArray is full" << endl ;
}
void array :: makeheap(int c)
{

	for ( int i = 1 ; i < c ; i++ )
	{
		int val = arr[i] ;
		int s = i ;
		int f = ( s - 1 ) / 2 ;
		while ( s > 0 && arr[f] < val )
		{
			arr[s] = arr[f] ;
			s = f ;
			f = ( s - 1 ) / 2 ;
		}
		arr[s] = val ;
	}
}
void array :: heapsort( )
{
	for ( int i = count - 1 ; i > 0 ; i-- )
	{
		int ivalue = arr[i] ;
		arr[i] = arr[0] ;
		arr[0]=ivalue;
		makeheap(i);

	}
}
void array :: display( )
{
	for ( int i = 0 ; i < count ; i++ )
		cout << arr[i] << "\t" ;
	cout << endl ;
}
void main( )
{
	array a ;

	a.add ( 11 ) ;
	a.add ( 2 ) ;
	a.add ( 9 ) ;
	a.add ( 13 ) ;
	a.add ( 57 ) ;
	a.add ( 25 ) ;
	a.add ( 17 ) ;
	a.add ( 1 ) ;
	a.add ( 90 ) ;
	a.add ( 3  ) ;
	a.makeheap(10) ;
	cout << "\nHeap Sort.\n" ;
	cout << "\nBefore Sorting:\n"  ;
	a.display( ) ;
	a.heapsort( ) ;
	cout << "\nAfter Sorting:\n" ;
	a.display( ) ;
}

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