#include <iostream>

using namespace std;

int main()
{
int n,gap(0),bn(0);
cin>>n;
while(n%2==0)n=n/2;
while(n>0)
{
if(n%2==1)
{ if(bn>gap)gap=bn;
bn=0;
}
else
bn++;
n=n/2;
}
cout<<gap<<endl;
return 0;

II Tasa

#include <iostream>

using namespace std;

int main()
{
int n,i,x,j,br=0,mr=0,jedan=0;
cin>>n;
int nuleij[100];
i=0;
while(n!=0)
{
x=n%2;
n=n/2;
nuleij[i]=x;
i++;
}
if(nuleij[0]=1)jedan=1;
for(j=1;j<i;j++)
{
if(nuleij[j]==1)jedan=1;
if((nuleij[j]==0) and (jedan==1))br++;
if((nuleij[j]==1) and (jedan==1) and (nuleij[j-1]==0))
{if(br>mr)mr=br;br=0;}
}
cout<<mr;
return 0;
}