#include #include using namespace std; using namespace atcoder; typedef long long int ll; typedef long double ld; #define FOR(i,l,r) for(ll i=l;i=l;i--) #define RREP(i,n) RFOR(i,0,n) #define ALL(x) x.begin(),x.end() #define PA pair #define F first #define S second #define BS(A,x) binary_search(ALL(A),x) #define LB(A,x) (ll)(lower_bound(ALL(A),x)-A.begin()) #define UB(A,x) (ll)(upper_bound(ALL(A),x)-A.begin()) #define COU(A,x) (UB(A,x)-LB(A,x)) #define sz(c) ((ll)(c).size()) //#include //namespace mp=boost::multiprecision; //using Bint=mp::cpp_int; templateusing min_priority_queue=priority_queue,greater>; templateostream&operator<<(ostream&os,pair&p){os<istream&operator>>(istream&is,pair&p){is>>p.F>>p.S;return is;} templateostream&operator<<(ostream&os,vector&v){REP(i,sz(v))os<istream&operator>>(istream&is,vector&v){for(T&in:v)is>>in;return is;} templatebool chmax(T&a,T b){if(abool chmin(T&a,T b){if(b>N; vectorS; REP(i,N){ string s;cin>>s; auto t=s;sort(ALL(t)); if(s==t)S.emplace_back(s); } N=sz(S); sort(ALL(S)); vectorDP(26); REP(i,N){ ll m=0; REP(c,S[i][0]-'a'+1)chmax(m,DP[c]); chmax(DP[S[i].back()-'a'],m+sz(S[i])); } ll ans=0; REP(i,26)chmax(ans,DP[i]); cout<