#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ld long double
#define ll long long
#define P pair<int,int>
#define fi first
#define se second
#define rep(i,n) for(int i=0;i<n;i++)
#define all(v) v.begin(),v.end()
#define pb push_back
#define eb emplace_back
template<class T>void chmax(T &a,T b){if(a<b)a=b;}
template<class T>void chmin(T &a,T b){if(a>b)a=b;}
constexpr int INF=1000000000000000000;
constexpr int mod=1000000007;
constexpr double eps=1e-8;
const double pi=acos(-1);
int dx[]={0,1,0,-1},dy[]={1,0,-1,0};
int Random(int mi,int ma){
    random_device rnd;
    mt19937 mt(rnd());//32bit
    //[mi,ma]
    uniform_int_distribution<int>engine(mi,ma);
    return engine(mt);
}
int gcd(int a,int b){
    if(b==0)return a;
    return gcd(b,a%b);
}
int lcm(int a,int b){
    return a/gcd(a,b)*b;
}
bool prime(int a){
    if(a==1)return false;
    for(int i=2;i*i<=a;i++){
        if(a%i==0)return false;
    }
    return true;
}
int modpow(int a,int b){
    if(b==0)return 1;
    if(b%2)return modpow(a,b-1)*a%mod;
    int memo=modpow(a,b/2);
    return memo*memo%mod;
}
vector<int>kaijo,invkaijo;
void init_fact(int n){
    kaijo.resize(n+1);
    invkaijo.resize(n+1);
    kaijo[0]=1;
    for(int i=1;i<=n;i++){
        kaijo[i]=kaijo[i-1]*i;
        kaijo[i]%=mod;
    }
    rep(i,n+1)invkaijo[i]=modpow(kaijo[i],mod-2);
}
int comb(int a,int b){
    if(a<b)return 0;
    if(a<0||b<0)return 0;
    return kaijo[a]*invkaijo[a-b]%mod*invkaijo[b]%mod;
}
int inv(int x){
    x=modpow(x,mod-2);
    return x;
}
bool comp(const string &s1,const string &s2){
    return s1.size()<s2.size();
}
struct RollingHash{
    const int MASK30=(1ll<<30)-1;
    const int MASK31=(1ll<<31)-1;
    const int MOD=(1ll<<61)-1;
    int Base=9973;
    vector<int>hash,power;
    int calcmod(int x){
        int res=(x>>61)+(x&MOD);
        if(res>=MOD)res-=MOD;
        return res;
    }
    int mul(int a,int b){
		int au=a>>31;
		int ad=a&MASK31;
		int bu=b>>31;
		int bd=b&MASK31;
		int mid=ad*bu+au*bd;
		int midu=mid>>30;
		int midd=mid&MASK30;
		return calcmod(au*bu*2+midu+(midd<<31)+ad*bd);
	}
    RollingHash(string s,int base){
        //Base=Random(1<<7,1<<9)
        Base=base;
        int n=s.size();
        hash.resize(n+1,0);
        power.resize(n+1,1);
        rep(i,n){
            hash[i+1]=(mul(hash[i],Base)+s[i])%MOD;
            power[i+1]=mul(power[i],Base)%MOD;
        }
    }
    int get_hash(int l,int r){
        //[l,r)
        return (hash[r]-mul(hash[l],power[r-l])+MOD)%MOD;
    }
};
int n;
string s[200010];
multiset<int>st[26];
bool used[1000010];
signed main(){
    cin.tie(0);ios::sync_with_stdio(false);
    cin>>n;
    rep(i,n){
        cin>>s[i];
        used[s[i].size()]=true;
    }
    sort(s,s+n,comp);
    int ans=0;
    rep(i,n){
        RollingHash rh(s[i],9973);
        int Bit=0;
        rep(j,s[i].size()+1){
            if(!used[s[i].size()-j+1]){
                if(j<s[i].size())Bit|=(1<<(s[i][j]-'a'));
                continue;
            }
            int hash=rh.get_hash(j,s[i].size());
            rep(k,26)if((Bit>>k)&1)ans+=st[k].count(hash);
            if(j<s[i].size())Bit|=(1<<(s[i][j]-'a'));
        }
        st[s[i][0]-'a'].insert(rh.get_hash(1,s[i].size()));
    }
    cout<<ans<<endl;
    return 0;
}

Measured memory_bytes: 26816