#if __INCLUDE_LEVEL__ == 0

#include __BASE_FILE__

namespace {

// https://atcoder.jp/contests/arc163/tasks/arc163_f/editorial
i64 f(const std::vector<int>& a) {
  int n = len(a);
  std::priority_queue<int> q;
  i64 ret = 0;
  for (const int i : rep(n)) {
    q.push(a[i]);
    q.push(a[i]);
    const int v = q.top();
    q.pop();
    ret += std::max(v - a[i], 0);
  }
  return ret;
}

void solve() {
  int n, k;
  scan(n, k);
  std::vector<int> a(n);
  scan(a);
  if (k == 1) {
    print(f(a));
  } else if (k == n) {
    i64 ans = inf<i64>();
    for (int _ = n; _--;) {
      chmin(ans, f(a));
      ranges::rotate(a, a.begin() + 1);
    }
    print(ans);
  } else if (k % 2 == 0) {
    print(0);
  } else {
    auto b = a;
    ranges::sort(b);
    if (ranges::adjacent_find(b) != b.end()) {
      print(0);
    } else {
      atcoder::fenwick_tree<int> f(n);
      i64 inv = 0;
      for (const int i : rep(n)) {
        const int t = static_cast<int>(ranges::lower_bound(b, a[i]) - b.begin());
        inv += f.sum(t, n);
        f.add(t, 1);
      }
      if (inv % 2 == 0) {
        print(0);
      } else {
        int ans = inf();
        for (const int i : rep(1, n)) {
          chmin(ans, b[i] - b[i - 1]);
        }
        print(ans);
      }
    }
  }
}

}  // namespace

int main() {
  std::ios::sync_with_stdio(false);
  std::cin.tie(nullptr);
  std::cout << std::setprecision(DBL_DECIMAL_DIG);

  int t;
  scan(t);
  while (t--) {
    solve();
  }
}

#else  // __INCLUDE_LEVEL__

#include <bits/stdc++.h>

namespace atcoder {

namespace internal {

template <class T>
using is_signed_int128 = typename std::conditional<std::is_same<T, __int128_t>::value ||
                                                       std::is_same<T, __int128>::value,
                                                   std::true_type, std::false_type>::type;

template <class T>
using is_unsigned_int128 = typename std::conditional<std::is_same<T, __uint128_t>::value ||
                                                         std::is_same<T, unsigned __int128>::value,
                                                     std::true_type, std::false_type>::type;

template <class T>
using make_unsigned_int128 =
    typename std::conditional<std::is_same<T, __int128_t>::value, __uint128_t, unsigned __int128>;

template <class T>
using is_integral =
    typename std::conditional<std::is_integral<T>::value || is_signed_int128<T>::value ||
                                  is_unsigned_int128<T>::value,
                              std::true_type, std::false_type>::type;

template <class T>
using is_signed_int =
    typename std::conditional<(is_integral<T>::value && std::is_signed<T>::value) ||
                                  is_signed_int128<T>::value,
                              std::true_type, std::false_type>::type;

template <class T>
using is_unsigned_int =
    typename std::conditional<(is_integral<T>::value && std::is_unsigned<T>::value) ||
                                  is_unsigned_int128<T>::value,
                              std::true_type, std::false_type>::type;

template <class T>
using to_unsigned = typename std::conditional<
    is_signed_int128<T>::value, make_unsigned_int128<T>,
    typename std::conditional<std::is_signed<T>::value, std::make_unsigned<T>,
                              std::common_type<T>>::type>::type;

template <class T>
using is_signed_int_t = std::enable_if_t<is_signed_int<T>::value>;

template <class T>
using is_unsigned_int_t = std::enable_if_t<is_unsigned_int<T>::value>;

template <class T>
using to_unsigned_t = typename to_unsigned<T>::type;

}  // namespace internal

}  // namespace atcoder

namespace atcoder {

template <class T>
struct fenwick_tree {
  using U = internal::to_unsigned_t<T>;

 public:
  fenwick_tree() : _n(0) {}
  explicit 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<U> data;

  U sum(int r) {
    U s = 0;
    while (r > 0) {
      s += data[r - 1];
      r -= r & -r;
    }
    return s;
  }
};

}  // namespace atcoder

template <class T, class U = T>
bool chmin(T& x, U&& y) {
  return y < x && (x = std::forward<U>(y), true);
}

template <class T, class U = T>
bool chmax(T& x, U&& y) {
  return x < y && (x = std::forward<U>(y), true);
}

template <std::signed_integral T = int>
T inf() {
  T ret;
  std::memset(&ret, 0x3f, sizeof(ret));
  return ret;
}

template <std::floating_point T>
T inf() {
  return std::numeric_limits<T>::infinity();
}

template <class T>
concept Range = std::ranges::range<T> && !std::convertible_to<T, std::string_view>;

template <class T>
concept Tuple = std::__is_tuple_like<T>::value && !Range<T>;

namespace std {

istream& operator>>(istream& is, Range auto&& r) {
  for (auto&& e : r) {
    is >> e;
  }
  return is;
}

istream& operator>>(istream& is, Tuple auto&& t) {
  return apply([&](auto&... xs) -> istream& { return (is >> ... >> xs); }, t);
}

ostream& operator<<(ostream& os, Range auto&& r) {
  for (string_view sep = ""; auto&& e : r) {
    os << exchange(sep, " ") << e;
  }
  return os;
}

ostream& operator<<(ostream& os, Tuple auto&& t) {
  const auto f = [&](auto&... xs) -> ostream& {
    [[maybe_unused]] string_view sep = "";
    ((os << exchange(sep, " ") << xs), ...);
    return os;
  };
  return apply(f, t);
}

}  // namespace std

void scan(auto&&... xs) { std::cin >> std::tie(xs...); }
void print(auto&&... xs) { std::cout << std::tie(xs...) << '\n'; }

template <class F>
class fix {
 public:
  explicit fix(F f) : f_(std::move(f)) {}

  decltype(auto) operator()(auto&&... xs) const {
    return f_(std::ref(*this), std::forward<decltype(xs)>(xs)...);
  }

 private:
  F f_;
};

inline auto rep(int l, int r) { return std::views::iota(std::min(l, r), r); }
inline auto rep(int n) { return rep(0, n); }
inline auto rep1(int l, int r) { return rep(l, r + 1); }
inline auto rep1(int n) { return rep(1, n + 1); }

using namespace std::literals;

namespace ranges = std::ranges;
namespace views = std::views;

using i64 = std::int64_t;

#define len(...) static_cast<int>(ranges::size(__VA_ARGS__))

#endif  // __INCLUDE_LEVEL__