#include <bits/stdc++.h>
using namespace std;
#define rep(i, n)  for(long long i=0;i<(long long)(n);i++)
#define REP(i,k,n) for(long long i=k;i<(long long)(n);i++)
#define all(a) a.begin(),a.end()
#define pb emplace_back
#define eb emplace_back
#define lb(v,k) (lower_bound(all(v),k)-v.begin())
#define ub(v,k) (upper_bound(all(v),k)-v.begin())
#define fi first
#define se second
#define pi M_PI
#define PQ(T) priority_queue<T>
#define SPQ(T) priority_queue<T,vector<T>,greater<T>>
#define dame(a) {out(a);return 0;}
#define decimal cout<<fixed<<setprecision(15);
#define dupli(a) {sort(all(a));a.erase(unique(all(a)),a.end());}
typedef long long ll;
typedef pair<ll,ll> P;
typedef tuple<ll,ll,ll> PP;
typedef tuple<ll,ll,ll,ll> PPP;
typedef multiset<ll> S;
using vi=vector<ll>;
using vvi=vector<vi>;
using vvvi=vector<vvi>;
using vvvvi=vector<vvvi>;
using vp=vector<P>;
using vvp=vector<vp>;
using vb=vector<bool>;
using vvb=vector<vb>;
const ll inf=1001001001001001001;
const ll INF=1001001001;
const ll mod=1000000007;
const double eps=1e-10;
template<class T> bool chmin(T&a,T b){if(a>b){a=b;return true;}return false;}
template<class T> bool chmax(T&a,T b){if(a<b){a=b;return true;}return false;}
template<class T> void out(T a){cout<<a<<'\n';}
template<class T> void outp(T a){cout<<'('<<a.fi<<','<<a.se<<')'<<'\n';}
template<class T> void outvp(T v){rep(i,v.size())cout<<'('<<v[i].fi<<','<<v[i].se<<')';cout<<'\n';}
template<class T> void outvvp(T v){rep(i,v.size())outvp(v[i]);}
template<class T> void outv(T v){rep(i,v.size()){if(i)cout<<' ';cout<<v[i];}cout<<'\n';}
template<class T> void outvv(T v){rep(i,v.size())outv(v[i]);}
template<class T> bool isin(T x,T l,T r){return (l)<=(x)&&(x)<=(r);}
template<class T> void yesno(T b){if(b)out("yes");else out("no");}
template<class T> void YesNo(T b){if(b)out("Yes");else out("No");}
template<class T> void YESNO(T b){if(b)out("YES");else out("NO");}
template<class T> void noyes(T b){if(b)out("no");else out("yes");}
template<class T> void NoYes(T b){if(b)out("No");else out("Yes");}
template<class T> void NOYES(T b){if(b)out("NO");else out("YES");}
void outs(ll a,ll b){if(a>=inf-100)out(b);else out(a);}
ll gcd(ll a,ll b){if(b==0)return a;return gcd(b,a%b);}
ll modpow(ll a,ll b){ll res=1;a%=mod;while(b){if(b&1)res=res*a%mod;a=a*a%mod;b>>=1;}return res;}
vi seg;
ll N;
void init(vi v){
    N=1;
    while(N<v.size())N*=2;
    seg=vi(N*2-1);
    rep(i,v.size())seg[i+N-1]=v[i];
    for(int i=N-2;i>=0;i--)seg[i]=seg[i*2+1]+seg[i*2+2];
}
void add(ll i,ll x){
    i=N+i-1;
    seg[i]+=x;
    while(i>0){
        i=(i-1)/2;
        seg[i]=seg[i*2+1]+seg[i*2+2];
    }
}
ll getsum(ll a,ll b,ll k,ll l,ll r){
    if(r<=a||b<=l)return 0;
    if(a<=l&&r<=b)return seg[k];
    ll c1=getsum(a,b,k*2+1,l,(l+r)/2);
    ll c2=getsum(a,b,k*2+2,(l+r)/2,r);
    return c1+c2;
}
int main(){
    ll n;cin>>n;
    vp v(n);
    rep(i,n){
        string s;cin>>s;
        ll res=0,k=1;
        for(int j=s.size()-1;j>=0;j--){
            if(s[j]=='.'){
                v[i]=P(j-s.size()+1,j-s.size()+1);
            }
            else{
                res+=k*(s[j]-'0');
                k*=10;
            }
        }
        while(res%2==0){
            res/=2;
            v[i].fi++;
        }
        while(res%5==0){
            res/=5;v[i].se++;
        }
    }
    vp x(n);
    rep(i,n)x[i]=P(-v[i].fi,-v[i].se);
    sort(all(v));reverse(all(v));
    sort(all(x));reverse(all(x));
    int w=0;
    ll ans=0;
    vi a;
    rep(i,n)a.pb(v[i].se);
    dupli(a);
    vi segt(a.size());
    init(segt);
    for(auto t:x){
        while(w<n&&v[w].fi>=t.fi){
            add(lb(a,v[w].se),1);
            w++;
        }
        ans+=getsum(lb(a,t.se),N,0,0,N);
    }
    rep(i,n)if(v[i].fi>=0&&v[i].se>=0)ans--;
    out(ans/2);
}

Measured memory_bytes: 11620