#include #define M_PI 3.14159265358979323846 using namespace std; //typedef //-------------------------#include #define M_PI 3.14159265358979323846 using namespace std; //conversion //------------------------------------------ inline int toInt(string s) { int v; istringstream sin(s); sin >> v; return v; } template inline string toString(T x) { ostringstream sout; sout << x; return sout.str(); } inline int readInt() { int x; scanf("%d", &x); return x; } //typedef //------------------------------------------ typedef vector VI; typedef vector VVI; typedef vector VS; typedef pair PII; typedef pair TIII; typedef long long LL; typedef unsigned long long ULL; typedef vector VLL; typedef vector VVLL; //container util //------------------------------------------ #define ALL(a) (a).begin(),(a).end() #define RALL(a) (a).rbegin(), (a).rend() #define PB push_back #define MP make_pair #define SZ(a) int((a).size()) #define SQ(a) ((a)*(a)) #define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i) #define EXIST(s,e) ((s).find(e)!=(s).end()) #define SORT(c) sort((c).begin(),(c).end()) //repetition //------------------------------------------ #define FOR(i,s,n) for(int i=s;i<(int)n;++i) #define REP(i,n) FOR(i,0,n) #define MOD 1000000007 #define rep(i, a, b) for(int i = a; i < (b); ++i) #define trav(a, x) for(auto& a : x) #define all(x) x.begin(), x.end() #define sz(x) (int)(x).size() typedef long long ll; typedef pair pii; typedef vector vi; const double EPS = 1E-8; #define chmin(x,y) x=min(x,y) #define chmax(x,y) x=max(x,y) const int INF = 100000000; struct Edge { int to, from; ll cost; Edge(int from, int to, ll cost): from(from), to(to), cost(cost) {} }; class UnionFind { public: vector par; vector siz; vector maxv; UnionFind(ll sz_): par(sz_), siz(sz_, 1LL) { for (ll i = 0; i < sz_; ++i) par[i] = i; } void init(ll sz_) { par.resize(sz_); siz.assign(sz_, 1LL); for (ll i = 0; i < sz_; ++i) par[i] = i; } ll root(ll x) { while (par[x] != x) { x = par[x] = par[par[x]]; } return x; } bool merge(ll x, ll y) { x = root(x); y = root(y); if (x == y) return false; if (siz[x] < siz[y]) swap(x, y); siz[x] += siz[y]; par[y] = x; return true; } bool issame(ll x, ll y) { return root(x) == root(y); } ll size(ll x) { return siz[root(x)]; } }; typedef vector> AdjList; AdjList graph; ll mod_pow(ll x, ll n, ll mod){ ll res = 1; while(n){ if(n&1) res = res * x; if(res > mod){ res %= mod; } x = x * x %mod; n >>= 1; } return res; } #define SIEVE_SIZE 5000000+10 bool sieve[SIEVE_SIZE]; void make_sieve(){ for(int i=0; i vector gauss_jordan(const vector>& A, const vector& b){ int n = A.size(); vector> B(n, vector(n+1)); for(int i=0; i abs(B[pivot][i])) pivot = j; } swap(B[i], B[pivot]); if(abs(B[i][i]) < EPS) return vector(); //解なし for(int j=i+1; j<=n; ++j) B[i][j] /= B[i][i]; for(int j=0; j x(n); for(int i=0; i vec; typedef vector mat; mat mul(mat &A, mat &B) { mat C(A.size(), vec((int)B[0].size())); for(int i=0; i 0) { if(n & 1) B = mul(B, A); A = mul(A, A); n >>= 1; } return B; } bool operator<(const pii& a, const pii& b){ if(a.first == b.first) return a.second < b.second; return a.first < b.first; } const int MAX = 510000; long long fac[MAX], finv[MAX], inv[MAX]; // テーブルを作る前処理 void COMinit() { fac[0] = fac[1] = 1; finv[0] = finv[1] = 1; inv[1] = 1; for (int i = 2; i < MAX; i++){ fac[i] = fac[i - 1] * i % MOD; inv[i] = MOD - inv[MOD%i] * (MOD / i) % MOD; finv[i] = finv[i - 1] * inv[i] % MOD; } } // 二項係数計算 long long COM(int n, int k){ if (n < k) return 0; if (n < 0 || k < 0) return 0; return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD; } int bit[1000010]; int sums(int i){ i++; int s = 0; while(i > 0){ s += bit[i]; i -= i & -i; } return s; } void add(int i, int x){ i++; while(i <= 1000010){ bit[i] += x; i += i & -i; } } long long extGCD(long long a, long long b, long long &x, long long &y) { if (b == 0) { x = 1; y = 0; return a; } long long d = extGCD(b, a%b, y, x); y -= a/b * x; return d; } ll GCD(ll a, ll b){ if(b == 0) return a; return GCD(b, a%b); } struct BipartiteMatching { vector< vector< int > > graph; vector< int > match, alive, used; int timestamp; BipartiteMatching(int n) : graph(n), alive(n, 1), used(n, 0), match(n, -1), timestamp(0) {} void add_edge(int u, int v) { graph[u].push_back(v); graph[v].push_back(u); } bool dfs(int idx) { used[idx] = timestamp; for(auto &to : graph[idx]) { int to_match = match[to]; if(alive[to] == 0) continue; if(to_match == -1 || (used[to_match] != timestamp && dfs(to_match))) { match[idx] = to; match[to] = idx; return true; } } return false; } int bipartite_matching() { int ret = 0; for(int i = 0; i < graph.size(); i++) { if(alive[i] == 0) continue; if(match[i] == -1) { ++timestamp; ret += dfs(i); } } return ret; } void output() { for(int i = 0; i < graph.size(); i++) { if(i < match[i]) { cout << i << "-" << match[i] << endl; } } } }; int main() { cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(15); string s; cin >> s; vector> G(26); REP(i,s.size()){ G[s[i]-'a'].push_back(i); } int arr[26]={0}; ll ans = 0; ll N = s.size(); for(int i=0; i