#include<bits/stdc++.h>
using namespace std;
#define sync ios_base::sync_with_stdio(false), cin.tie(NULL)
#define F first
#define S second
#define pb emplace_back
#define mt make_tuple
#define gcd __gcd
#define PI 3.141592653589
// Input
#define in(a) scanf("%d",&a)
#define in2(a,b) scanf("%d%d",&a,&b)
#define in3(a,b,c) scanf("%d%d%d",&a,&b,&c)
#define llin(a) cin >> a
#define inl(a) scanf("%lld",&a)
#define read(v,i,n) for(i=0;i<n;i++)in(v[i])
#define twod(mat,i,j,n,m) rep(i,n){rep(j,m)in(mat[i][j]);}
#define sc(ch) scanf("%c",&ch)
#define sstr(str) scanf("%s",str)
// Output
#define pr(a) printf("%d ",a)
#define pr2(a,b) printf("%d %d\n",a,b)
#define pr3(a,b,c) printf("%d %d %d\n",a,b,c)
#define out(a) printf("%d\n",a)
#define outl(a) printf("%lld\n",a)
#define llpr(a) cout << a << " "
#define llout(a) cout << a << "\n"
#define yes printf("YES\n")
#define no printf("NO\n")
#define lin printf("\n")
// Iterator
#define lp(i,a,b) for(i=a;i<b;i++)
#define rep(i,n) for(i=0;i<n;i++)
#define all(vec) vec.begin(),vec.end()
#define lower(v,k) lower_bound(v.begin(),v.end(),k)-v.begin()
#define upper(v,k) upper_bound(v.begin(),v.end(),k)-v.begin()
#define tf(mytuple) get<0>(mytuple)
#define ts(mytuple) get<1>(mytuple)
#define tt(mytuple) get<2>(mytuple)
// Debug
#define dbg(v,i,n) for(i=0;i<n;i++)pr(v[i]); lin
#define what(x) cerr << #x << " : " << x << "\n"
#define ck printf("continue\n")
#define debug(args...) { string _s = #args; replace(_s.begin(), _s.end(), ',', ' '); stringstream _ss(_s); istream_iterator<string> _it(_ss); err(_it, args); }
void err(istream_iterator<string> it) {}
template<typename T, typename... Args>
void err(istream_iterator<string> it, T a, Args... args)
{
	cerr << *it << " = " << a << "\n";
	err(++it, args...);
}
// Data Type
#define ll long long int
#define ii pair<int,int>
#define pli pair<ll,int>
#define triple tuple<int,int,int>
#define vi vector<int>
#define vii vector<pair<int,int> >
#define vvi vector<vector<int> >
#define viii vector<pair<pair<int,int>,int> >
#define vvii vector<vector<pair<int,int> > >
#define M 1000000007
#define N 200005
ll start[N],last[N];
ll nc2(ll m)
{
    ll temp=m;
    temp*=(m-1);
    temp/=2;
    return temp;
}
map<ll,vector<pair<ll,ll> > > ad;
ll compute(int i)
{
    if(ad[i].size()==0)
        return 0;
    ll l,r,a,b;
    sort(all(ad[i]));
    tie(l,r)=ad[i][0];
    ll temp=0;
    int j;
    rep(j,ad[i].size())
    {
        tie(a,b)=ad[i][j];
        if(a<=r+1)
            r=max(r,b);
        else
            temp+=(r-l+1),l=a,r=b;
    }
    temp+=(r-l+1);
    return temp;
}
int main()
{
    ll n,x,d,g,k;
    int i;
    cin >> n >> x >> d;
    if(d==0)
    {
        if(x==0)
            out(1);
        else
            out(n+1);
        exit(0);
    }
    g=gcd(x,d);
    x/=g,d/=g;
    if(d<0)
        d=-d,x=-x;
    ll ans=0;
    set<int> st;
    set<int> :: iterator itr;
    rep(i,n+1)
    {
        start[i]=nc2(i);
        last[i]=nc2(n)-nc2(n-i);
        k=i,k*=x,k/=d;
        start[i]+=k;
        last[i]+=k;
        g=i,g*=x,g%=d;
        if(g<0)
            g+=d;
        st.insert(g);
        ad[g].pb(start[i],last[i]);
    }
    itr=st.begin();
    while(itr!=st.end())
        ans+=compute(*itr),itr++;
    llout(ans);
}








Measured memory_bytes: 34560