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for(count=0;count<31;count++) // 31 if it is a 32 bit integer
{
if((N>>count)&1==1)
{
print(the position is count)
break;
}
}

Here is recursive program which is easiest way

int func(int);
void main()
{
	int no=104;
	printf("%d",func(no));
}
int func(int no)
{
	if(no%2==1)
		return 1;
	return func(no/2)+1;
}

If N is the number, N&-N will give you the first bit set

#include<stdio.h>
#include <math.h>
main()
{
float n = 4.0;
printf("\nThe bit position is at: %f\n", sqrt(n)+1);
}

Here is another solution: geeksforgeeks org/ ?p=555
log2(n&-n)+1

However it is costly because of using log2.

little optimized

int bitset(unsigned long num)
{
    int count = 0;
    while(num) {
	switch (num & 0xf) {
	case 1:
	case 3:
	case 5:
	case 7:
	    return count + 1;
	case 2:
	    return count + 2;
	case 4:
	    return count + 3;
	case 8:
	    return count + 4;

	default:
	    break;
	}
	num >>= 4;
	count += 4;
    }
}

int getPos(int x)
{
int count = 0, y = 0;
while(!y)
{
y = x & 01;
x = x >> 1;
count++;
}
return count;
}

and

int count_bits(int num){

     int count = 0;
     while(((num & 1) != 1)  && count < (sizeof(int) * 8){
           num = num >> 1;
           count++;
     }
     if(num & 1)
          return count;
     return -1;
}

#include <stdio.h>

int bitset(int n)
{
    int i=1,pos=1;
    for(;i<sizeof(int)*8;i*=2,pos++)
    {
        if((n&i)==i)
        return pos;
    }
    return -1;
}

int main()
{
    int n,pos;
    printf("Enter no. to find its first set bit position from the right side: ");
    scanf("%d",&n);
    pos=bitset(n);
    if(pos==-1)
    printf("\nNo. is zero");
    else
    printf("\nFirst set bit position from the right side: %d",pos);
}

count =1;
while(((num|1) != num) && count++)
num = num>>1;
print count;

int i=0;
for(n;n>0;n/=2)
{i++;
if((n%2)==1)
break;
}
cout<<"position="<<i;

#include<iostream>
#include<math.h>
using namespace std;
int main(){
	int a=2,count=0,num,flag=0;
	cin>>num;
	while(1){
		if(num==0){
			cout<<"No bit will set to 1:\n";
			break;
			}
		else
			{
			flag=num & (int)pow(a,count);		
			if(flag!=0){
				cout<<count+1<<"\n";
				break;
				}
			count++;			
			}

		}
	return 0;
}