```
using namespace std;
int main()
{
long int n,sum=0;
cin>>n;
long int k=n;
while(k>=5)
{
k=k/5;
sum=sum+k;
}
cout<<sum<<endl;
return 0;
}
```

Nothing wrong here??

```
using namespace std;
int main()
{
long int n,sum=0;
cin>>n;
long int k=n;
while(k>=5)
{
k=k/5;
sum=sum+k;
}
cout<<sum<<endl;
return 0;
}
```

Nothing wrong here??

Almost everything (except the algorithm)…

Why are you doing this?

```
cout << "Enter the value of n" << endl;
```

And this?

```
cout<<"no. of zeros ="<<sum<<endl;
```

And this?

`system("pause");`