A_Array_and_Peaks.cpp

#include <bits/stdc++.h>
using namespace std;
#define max(a, b) ((a) > (b) ? (a) : (b))
#define min(a, b) ((a) < (b) ? (a) : (b))
#define gcd(a, b) __gcd(a, b)
#define lcm(a, b) (a * b) / gcd(a, b)
#define GOLD ((1 + sqrt(5)) / 2)
const double PI = 3.14159265358979323846264338327950288419716939937510582097494459230;

void swaps(char *x, char *y)
{
    char temp;
    temp = *x;
    *x = *y;
    *y = temp;
}

void swapi(int *a, int *b)
{
    int temp;
    temp = *a;
    *a = *b;
    *b = temp;
}

void compute()
{
    int n, k;
    cin >> n >> k;

    if (k > (n - 1) / 2)
    {
        cout << "-1\n";
        return;
    }

    int f = 1, r = n;
    bool b = true;

    while (n--)
    {
        if (b || k <= 0)
        {
            cout << f << " ";
            f++;
        }
        else
        {
            cout << r << " ";
            --k, --r;
        }
        b = !b;
    }
    cout << "\n";
}

int main()
{
#ifdef debug
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    freopen("log.txt", "w", stderr);
#endif
    int t;
    scanf("%d", &t);
    while (t--)
    {
        compute();
    }
#ifdef debug
    fprintf(stdout, "\nTIME: %.3lf sec\n", (double)clock() / (CLOCKS_PER_SEC));
#endif
    return 0;
}