#include <string>
#include <vector>
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<stack>
#include<queue>
#include<cmath>
#include<algorithm>
#include<functional>
#include<list>
#include<deque>
#include<bitset>
#include<set>
#include<map>
#include<unordered_map>
#include<unordered_set>
#include<cstring>
#include<sstream>
#include<complex>
#include<iomanip>
#include<numeric>
#include<cassert>
#include<random>
#define X first
#define Y second
#define pb push_back
#define rep(X,Y) for (int (X) = 0;(X) < (int)(Y);++(X))
#define reps(X,S,Y) for (int (X) = (int)(S);(X) < (int)(Y);++(X))
#define rrep(X,Y) for (int (X) = (int)(Y)-1;(X) >=0;--(X))
#define rreps(X,S,Y) for (int (X) = (int)(Y)-1;(X) >= (int)(S);--(X))
#define repe(X,Y) for ((X) = 0;(X) < (Y);++(X))
#define peat(X,Y) for (;(X) < (Y);++(X))
#define all(X) (X).begin(),(X).end()
#define rall(X) (X).rbegin(),(X).rend()
#define eb emplace_back
#define UNIQUE(X) (X).erase(unique(all(X)),(X).end())
#define Endl endl
#define NL <<"\n"
#define cauto const auto

using namespace std;
using ll=long long;
using pii=pair<int,int>;
using pll=pair<ll,ll>;
template<class T> using vv=vector<vector<T>>;
template<class T> inline bool MX(T &l,const T &r){return l<r?l=r,1:0;}
template<class T> inline bool MN(T &l,const T &r){return l>r?l=r,1:0;}
//#undef NUIP
#ifdef NUIP
#include "benri.h"
#else
#define out(args...)
#endif
#ifdef __cpp_init_captures
template<typename T>vector<T> table(int n, T v){ return vector<T>(n, v);}
template <class... Args> auto table(int n, Args... args){auto val = table(args...); return vector<decltype(val)>(n, move(val));}
#endif
template<class A,class B> pair<A,B> operator+(const pair<A,B> &p,const pair<A,B> &q){ return {p.X+q.X,p.Y+q.Y};}
template<class A,class B,class C,class D> pair<A,B>& operator+=(pair<A,B> &p,const pair<C,D> &q){ p.X+=q.X; p.Y+=q.Y; return p;}
template<class A,class B> pair<A,B> operator-(const pair<A,B> &p,const pair<A,B> &q){ return {p.X-q.X,p.Y-q.Y};}
template<class A,class B,class C,class D> pair<A,B>& operator-=(pair<A,B> &p,const pair<C,D> &q){ p.X-=q.X; p.Y-=q.Y; return p;}
template<class A,class B> istream& operator>>(istream &is, pair<A,B> &p){ is>>p.X>>p.Y; return is;}
template<class T=ll> T read(){ T re; cin>>re; return move(re);}
template<class T=ll> T read(const T &dec){ T re; cin>>re; return re-dec;}
template<class T=ll> vector<T> readV(const int sz){ vector<T> re(sz); for(auto &x:re) x=read<T>(); return move(re);}
template<class T=ll> vector<T> readV(const int sz, const T &dec){ vector<T> re(sz); for(auto &x:re) x=read<T>(dec); return move(re);}
vv<int> readG(const int &n,const int &m){ vv<int> g(n); rep(_,m){ cauto a=read<int>(1),b=read<int>(1); g[a].pb(b); g[b].pb(a);} return move(g);}
vv<int> readG(const int &n){ return readG(n,n-1);}
const ll MOD=1e9+7; //998244353

const int nn=212345;
ll bit[nn+1];

ll sum(int i){ ++i;
  ll s=0;
  while(i>0){
    s+=bit[i];
    i-=i&-i;
  }
  return s;
}

void add(int i,ll x){ ++i; ++i;
  while(i<=nn){
    bit[i]+=x;
    i+=i&-i;
  }
}

int main(){
  ios_base::sync_with_stdio(false); cin.tie(0);
  cout<<fixed<<setprecision(0);
	cauto n=read();
	auto ss=readV<string>(n);
	for(auto &s:ss) reverse(all(s));
	sort(all(ss));
	vector<pii> ints(n);
	rep(i,n){
		auto s=ss[i];
		s.back()='a'-1;
		ints[i].X=lower_bound(all(ss),s)-ss.begin();
		s.back()='z'+1;
		ints[i].Y=lower_bound(all(ss),s)-ss.begin();
	}
	out(ss,ints,1);
	ll re=0;
	reps(c,'a','z'+1){
		fill(bit,bit+212345+1,0);
		vector<pii> ps(n);
		rep(i,n){
			auto &[cnt,ind]=ps[i];
			ind=i;
			for(char d:ss[i])if(c==d) ++cnt;
		}
		sort(rall(ps));
		for(int l=0,r=0;l<n;l=r){
			while(r<n && ps[l].X==ps[r].X) ++r;
			out(l,r,1);
			reps(i,l,r) add(ps[i].Y,1);
			reps(i,l,r){
				auto ind=ps[i].Y;
				if(ss[ind].back()!=c) continue;
				auto p=ints[ind];
				// if(sum(p.Y)-sum(p.X)) out(sum(p.Y)-sum(p.X),p,ind,c,1);
				re+=sum(p.Y)-sum(p.X);
			}
		}
	}
	cout<< re-n NL;
  return 0;
}


Measured memory_bytes: 14224