#include #include #include #include #include #include namespace atcoder { namespace internal { #ifndef _MSC_VER template using is_signed_int128 = typename std::conditional::value || std::is_same::value, std::true_type, std::false_type>::type; template using is_unsigned_int128 = typename std::conditional::value || std::is_same::value, std::true_type, std::false_type>::type; template using make_unsigned_int128 = typename std::conditional::value, __uint128_t, unsigned __int128>; template using is_integral = typename std::conditional::value || is_signed_int128::value || is_unsigned_int128::value, std::true_type, std::false_type>::type; template using is_signed_int = typename std::conditional<(is_integral::value && std::is_signed::value) || is_signed_int128::value, std::true_type, std::false_type>::type; template using is_unsigned_int = typename std::conditional<(is_integral::value && std::is_unsigned::value) || is_unsigned_int128::value, std::true_type, std::false_type>::type; template using to_unsigned = typename std::conditional< is_signed_int128::value, make_unsigned_int128, typename std::conditional::value, std::make_unsigned, std::common_type>::type>::type; #else template using is_integral = typename std::is_integral; template using is_signed_int = typename std::conditional::value && std::is_signed::value, std::true_type, std::false_type>::type; template using is_unsigned_int = typename std::conditional::value && std::is_unsigned::value, std::true_type, std::false_type>::type; template using to_unsigned = typename std::conditional::value, std::make_unsigned, std::common_type>::type; #endif template using is_signed_int_t = std::enable_if_t::value>; template using is_unsigned_int_t = std::enable_if_t::value>; template using to_unsigned_t = typename to_unsigned::type; } // namespace internal } // namespace atcoder #include #include namespace atcoder { // Reference: https://en.wikipedia.org/wiki/Fenwick_tree template struct fenwick_tree { using U = internal::to_unsigned_t; public: fenwick_tree() : _n(0) {} fenwick_tree(int n) : _n(n), data(n) {} void add(int p, T x) { assert(0 <= p && p < _n); p++; while (p <= _n) { data[p - 1] += U(x); p += p & -p; } } T sum(int l, int r) { assert(0 <= l && l <= r && r <= _n); return sum(r) - sum(l); } private: int _n; std::vector data; U sum(int r) { U s = 0; while (r > 0) { s += data[r - 1]; r -= r & -r; } return s; } }; } // namespace atcoder using lint = long long; void solve() { int n, q; std::cin >> n >> q; std::vector xs(n); for (auto& x : xs) { std::cin >> x; --x; } std::vector fore(n + 1, 0); // [0, i) { atcoder::fenwick_tree bit(n); for (int i = 0; i < n; ++i) { fore[i + 1] = fore[i] + bit.sum(xs[i] + 1, n); bit.add(xs[i], 1); } } std::vector back(n + 1, 0); // [i, n) { atcoder::fenwick_tree bit(n); for (int i = n - 1; i >= 0; --i) { back[i] = back[i + 1] + bit.sum(0, xs[i]); bit.add(xs[i], 1); } } while (q--) { int l, r; std::cin >> l >> r; --l; // [l, r) // [0, l)と[r, n) lint ans = fore[l] + back[r]; std::vector inv(n, 0); std::vector fs(n, 0); // [i, n) for (int i = 0; i < l; ++i) ++fs[xs[i]]; { lint acc = 0; for (int i = n - 1; i >= 0; --i) { inv[i] += acc; acc += fs[i]; fs[i] = acc; } } { std::vector bs(n, 0); for (int i = r; i < n; ++i) ++bs[xs[i]]; lint acc = 0; for (int i = 0; i < n; ++i) { if (i + 1 < n) ans += fs[i + 1] * bs[i]; inv[i] += acc; acc += bs[i]; } } ans += *std::min_element(inv.begin(), inv.end()) * (r - l); std::cout << ans << "\n"; } } int main() { std::cin.tie(nullptr); std::ios::sync_with_stdio(false); solve(); return 0; }