#include<bits/stdc++.h>
using namespace std;
using ll=long long;
template<class T,class U> inline bool chmin(T&x,U y){if(x>y){x=y;return true;}return false;}
template<class T,class U> inline bool chmax(T&x,U y){if(x<y){x=y;return true;}return false;}
#define fr(i,n) for(int i=0;i<(n);++i)
#define Fr(i,n) for(int i=1;i<=(n);++i)
#define ifr(i,n) for(int i=(n)-1;i>=0;--i)
#define iFr(i,n) for(int i=(n);i>0;--i)

struct modint{
    using i64=long long;
    i64 a;
    static constexpr i64 MOD=1e9+7;
    constexpr modint():a(){}
    constexpr modint(i64 a_):a(a_%MOD){
        if(a<0) a+=MOD;
    }
    constexpr modint inv()const noexcept{
        i64 n=1,m=MOD-2,A=a;
        while(m){
            if(m&1)(n*=A)%=MOD;
            (A*=A)%=MOD;
            m>>=1;
        }
        modint y;
        y.a=n;
        return y;
    }
    constexpr modint operator+()noexcept{
        return *this;
    }
    constexpr modint operator-()noexcept{
        modint tmp{};
        if(a) tmp.a=MOD-a;
        return tmp;
    }
    constexpr modint& operator++()noexcept{
        ++a;
        if(a==MOD) a=0;
        return *this;
    }
    constexpr modint& operator--()noexcept{
        if(a) --a;
        else a=MOD-1;
        return *this;
    }
    constexpr modint operator++(int)noexcept{
        modint tmp=*this;
        ++a;
        if(a==MOD) a=0;
        return tmp;
    }
    constexpr modint operator--(int)noexcept{
        modint tmp=*this;
        if(a) --a;
        else a=MOD-1;
        return tmp;
    }
    constexpr bool operator==(const modint& x)const noexcept{
        return a==x.a;
    }
    constexpr bool operator!=(const modint& x)const noexcept{
        return a!=x.a;
    }
    constexpr modint operator+(const modint& x)const noexcept{
        modint y;
        y.a=a+x.a;
        if(y.a>=MOD) y.a-=MOD;
        return y;
    }
    constexpr modint operator-(const modint& x)const noexcept{
        modint y;
        y.a=a-x.a;
        if(y.a<0) y.a+=MOD;
        return y;
    }
    constexpr modint operator*(const modint& x)const noexcept{
        modint y;
        y.a=(a*x.a)%MOD;
        return y;
    }
    constexpr modint operator/(const modint& x)const noexcept{
        modint y;
        y.a=(a*x.inv().a)%MOD;
        return y;
    }
    constexpr modint& operator+=(const modint& x)noexcept{
        a+=x.a;
        if(a>=MOD) a-=MOD;
        return *this;
    }
    constexpr modint& operator-=(const modint& x)noexcept{
        a-=x.a;
        if(a<0) a+=MOD;
        return *this;
    }
    constexpr modint& operator*=(const modint& x)noexcept{
        (a*=x.a)%=MOD;
        return *this;
    }
    constexpr modint& operator/=(const modint& x)noexcept{
        (a*=x.inv().a)%=MOD;
        return *this;
    }
};
istream& operator>>(istream &in,modint& x)noexcept{
    static int_fast64_t a_;
    in>>a_;
    modint y(a_);
    x=y;
    return in;
}
ostream& operator<<(ostream &out,const modint& x)noexcept{
    out<<x.a;
    return out;
}
constexpr modint pwr(int_fast64_t a,int_fast64_t b)noexcept{
    modint _;
    int_fast64_t n=1,A=a;
    while(b){
        if(b&1) (n*=A)%=modint::MOD;
        (A*=A)%=modint::MOD;
        b>>=1;
    }
    _.a=n;
    return _;
}

int b=100007,B=100003;

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    ll n,M{},ans{};
    cin>>n;
    vector<int> p(n);
    iota(p.begin(),p.end(),0);
    vector<string> s(n);
    for(auto&c:s) cin>>c,chmax(M,c.length());
    sort(p.begin(),p.end(),[&](int i,int j){
        return s[i].length()<s[j].length();
    });
    vector<unordered_map<long long,unsigned long long>> mp(M);
    fr(i,n){
        int j=p[i];
        int L=s[j].length();
        vector<modint> h(L+1),H(L+1);
        ifr(l,L){
            if(!l) mp[L-1][h[1].a*H[1].a]|=(1ull<<(s[j][0]-'a'));
            h[l]=h[l+1]*b;
            h[l]+=s[j][l];
            H[l]=H[l+1]*B;
            H[l]+=s[j][l]*5;
        }
        unsigned long long st=1ull<<(s[j][0]-'a');
        Fr(l,L-1){
            st|=(1ull<<(s[j][l]-'a'));
            auto X=st&mp[L-l-1][h[l+1].a*H[l+1].a];
            fr(T,26) if((X>>T)&1) ++ans;
        }
    }
    cout<<ans<<'\n';
}

Measured memory_bytes: 133776