程序执行不了

#include<bits/stdc++.h>
using namespace std;
int n,a[10005],b,c,al,bl,ans=0,sum=0;
int main()
{ 
    cin>>n;
    for(int i=1;i<=n;i++)
    {
    	for(;i>0;i/=2)
    	{
    		a[++b]=i%2;
    		if(a[b]==1)al++;
    		if(a[b]==0)bl++;
		}
		if(al>bl)ans++;
		if(bl>al)sum++;
		al=0;
		bl=0;
	}
	cout<<ans<<" "<<sum;
	return 0;
}