
```
#include <iostream>
using namespace std;
int main(){
    int n,a=1,b=0;
    cin>>n;
    for(int i=a;i<=n;i*=2){
        b++;
    }
    cout<<b;
    return 0;
}
```

```
#include <iostream>
using namespace std;
int main(){
    int n,a=1,b=0;
    cin>>n;
    for(int i=a;i<=n;i*=2){
        a*=2;
        b++;
    }
    cout<<b;
    return 0;
```

```
#include <iostream>
using namespace std;
int main(){
    int n,a=1,b=0;
    cin>>n;
    while(a<=n){
        a*=2;
        b++;
    }
    cout<<b;
    return 0;
}
```


