LOHONG C++

#include <bits/stdc++.h>
using namespace std;

int s,n,x,a[10]={1,0,0,0,1,0,1,0,2,1};
void nhap()
{
    //scanf("%d",&n);
    cin>>n;
}

void giai()
{
    s=0;
    while(n>0)
    {
        x=n%10;
        n/=10;
        s+=a[x];
    }
    printf("%d",s);
}

int main()
{
    freopen("lohong.inp","r",stdin);
    freopen("lohong.out","w",stdout);
    nhap();
    giai();
}