#include using namespace std::literals::string_literals; using i64 = std::int_fast64_t; using std::cout; using std::cerr; using std::endl; using std::cin; template std::vector make_v(size_t a){return std::vector(a);} template auto make_v(size_t a,Ts... ts){ return std::vector(ts...))>(a,make_v(ts...)); } #define NDEBUG template class segment_tree { using value_type = Monoid; using size_type = size_t; using binary_function = std::function; using checker = std::function; const size_type size_; size_type height_; const value_type id; const binary_function bi_func; std::vector data; private: const size_type get_height(const size_type& size) const { size_type height = 1; while(1 << height <= size) height++; return height; } const size_type base_size() const { return 1 << height_; } void meld(const size_type& index) { data[index] = bi_func(data[index << 1 ^ 0], data[index << 1 ^ 1]); } public: segment_tree(const size_type& size, const binary_function& bi_func, const value_type& id) : size_(size), bi_func(bi_func), id(id) { height_ = get_height(size); data.assign(base_size() << 1, id); } value_type fold(size_type left, size_type right) { value_type l_value = id, r_value = id; for(left += base_size(), right += base_size(); left < right; left >>= 1, right >>= 1) { if(left & 1) l_value = bi_func(l_value, data[left++]); if(right & 1) r_value = bi_func(data[--right], r_value); } return bi_func(std::move(l_value), std::move(r_value)); } void update(size_type index, const value_type& value) { index += base_size(); data[index] = bi_func(data[index], value); while(index >>= 1) meld(index); } void change(size_type index, const value_type& value) { index += base_size(); data[index] = value; while(index >>= 1) meld(index); } const size_type search(const size_type & left, const checker & check) { value_type val = id; size_t base_size_ = base_size(); auto find = [&](auto&& find, size_type k, size_type l, size_type r) -> int { if(l + 1 == r) { val = bi_func(val, data[k]); return (check(val) ? k - base_size_ : -1); } const size_type mid = (l + r) >> 1; if(mid <= left) return find(find, k << 1 ^ 1, mid, r); if(left <= l and !check(bi_func(val, data[k]))) { val = bi_func(val, data[k]); return -1; } const int left_ret = find(find, k << 1 ^ 0, l, mid); if(left_ret == -1) return find(find, k << 1 ^ 1, mid, r); return left_ret; }; return find(find, 1, 0, base_size_); } value_type operator[](const size_type& index) const { return data[index + base_size()]; } const size_type size() const { return size_; } const bool empty() const { return data.empty(); } }; int main() { int n; scanf("%d", &n); std::vector s(n); for(int i = 0; i < n; i++) cin >> s[i]; std::vector a(n - 1); for(int i = 0; i < n - 1; i++) { for(int j = 0; j < std::min(s[i + 1].size(), s[i].size()); j++) { if(s[i][j] != s[i + 1][j]) break; a[i] = j + 1; } } i64 ans = 0; for(auto v: s) ans += v.size(); auto f = [](int a, int b) { return std::min(a, b); }; segment_tree seg((int)1e5 + 1, f, (int)a.size()); std::vector nxt(a.size()); for(int i = (int)a.size() - 1; i >= 0; i--) { nxt[i] = seg.fold(0, a[i]); seg.change(a[i], i); } #ifndef NDEBUG for(auto v: a) cout << v << " "; cout << endl; for(auto v: nxt) cout << v << " "; cout << endl; #endif for(int i = 0; i < a.size(); i++) { int now = i; while(now < a.size()) { i64 S = now - i + 2, T = nxt[now] - i + 1; i64 len = (S + T) * (T - S + 1) >> 1; ans += len * a[now]; now = nxt[now]; } } printf("%lld\n", ans); return 0; }