83 lines
2.5 KiB
C
83 lines
2.5 KiB
C
|
/*
|
||
|
|
* C Program to Use Bitwise Operations to Count the Number of
|
||
|
|
* Leading Zero's in a Number x
|
||
|
|
*/
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#define NUM_BITS_INT (sizeof(int)*8)
|
||
|
|
int find(int);
|
||
|
|
|
||
|
|
void main()
|
||
|
|
{
|
||
|
|
int n, i, a, count = 0, flag = 1, m = 1, j, cmp;
|
||
|
|
printf("Enter the number\n");
|
||
|
|
scanf("%d", &n);
|
||
|
|
a = n >> 31 & 1;
|
||
|
|
if (a == 0)
|
||
|
|
{
|
||
|
|
for (i = (NUM_BITS_INT)-1; i >= 0; i--)
|
||
|
|
{
|
||
|
|
a = (n >> i)& 1;
|
||
|
|
if (a == 0)
|
||
|
|
{
|
||
|
|
count++;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
for (j = n + 1;; j++)
|
||
|
|
{
|
||
|
|
cmp = find(j);
|
||
|
|
if (cmp == (((NUM_BITS_INT)-1) - count) + 1)
|
||
|
|
{
|
||
|
|
printf("next higher power -> %d\n", j);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
for (i = (NUM_BITS_INT)-1; i >= 0; i--)
|
||
|
|
{
|
||
|
|
a = (n >> i)& 1;
|
||
|
|
if (a == 1)
|
||
|
|
{
|
||
|
|
count++;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
for (j = n + 1;; j++)
|
||
|
|
{
|
||
|
|
cmp = find(j);
|
||
|
|
if (cmp == (((NUM_BITS_INT)- 1) - count))
|
||
|
|
{
|
||
|
|
printf("next higher power -> %d\n", j);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* To find trailing zero's */
|
||
|
|
int find(int n)
|
||
|
|
{
|
||
|
|
int count = 0, a, flag = 1, i;
|
||
|
|
for (i = 0; i <= (NUM_BITS_INT) - 1; i++)
|
||
|
|
{
|
||
|
|
a = (n >> i) & 1;
|
||
|
|
if (a == 1 && flag == 1)
|
||
|
|
{
|
||
|
|
return count;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
count++;
|
||
|
|
flag = 1;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|