reshmi_G

 Profile Answers by reshmi_G 

• Jul 21st, 2011

 

Powers of 2 will have msb as 1 and all other bits as 0. This can be checked by left-shifting the number by 1 and checking if the result is 0 .

if((b<<1)==0)
"power of two"

Revathy

• Aug 10th, 2011

 

Let us consider the binary numbers

ex:let n=8 let n=6

1000 0110
n-1=7 n-1=5

0111 0101

n&(n-1) n&(n-1)

1000 0110
0111 0101

0000 0100

with this example we can infer that for the number which is power of two,by taking its preceding number (i.e..,n-1) and performing &(and) operation we get zero.and for numbers which are not,if we perform the same operation we get non-zero value :)

Code
#include<stdio.h>


#include<conio.h>


int power_of_two(int);


void main()


{


  int n;


  printf("enter the number");


  scanf("%d",&n);


  power_of_two(n);


}


int power_of_two(int n)


{


 if((n&(n-1))==0)


    printf("the number is power of two");


 else


    printf("it is not power of two");


getch();


}

sreethu

• Aug 10th, 2011

 

This is based on binary numbers

Code
#include<stdio.h>


#include<conio.h>


int power_of_two(int);


void main()


{


  int n;


  printf("enter the number");


  scanf("%d",&n);


  power_of_two(n);


}


int power_of_two(int n)


{


 if((n&(n-1))==0)


    printf("the number is power of two");


 else


    printf("it is not power of two");


getch();


}

Surender Reddy G

• Jun 2nd, 2015

 

Code
int x=64;


if(x&&(x&(x-1))) printf(" x is not the power of 2");


else printf("x is power of 2");