CodeForces 361B

B. Levko and Permutation
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Levko loves permutations very much. A permutation of length n is a sequence of distinct positive integers, each is at most n.

Let’s assume that value gcd(a, b) shows the greatest common divisor of numbers a and b. Levko assumes that element pi of permutation p1, p2, ... , pn is good if gcd(i, pi) > 1. Levko considers a permutation beautiful, if it has exactly k good elements. Unfortunately, he doesn’t know any beautiful permutation. Your task is to help him to find at least one of them.

Input

The single line contains two integers n and k (1 ≤ n ≤ 1050 ≤ k ≤ n).

Output

In a single line print either any beautiful permutation or -1, if such permutation doesn’t exist.

If there are multiple suitable permutations, you are allowed to print any of them.

Examples
input
4 2
output
2 4 3 1
input
1 1
output
-1
Note

In the first sample elements 4 and 3 are good because gcd(2, 4) = 2 > 1 and gcd(3, 3) = 3 > 1. Elements 2 and 1 are not good because gcd(1, 2) = 1 and gcd(4, 1) = 1. As there are exactly 2 good elements, the permutation is beautiful.

The second sample has no beautiful permutations.


#include <cstdio>
using namespace std;

int main()
{
    int n, m;
    scanf("%d%d", &n, &m);
        if (n == m)
            printf("-1\n");
        else{
            printf("%d ", n - m);
            for (int i = 1; i < n - m; i++)
                printf("%d ", i);
            for (int i = n - m + 1; i <= n; i++)
                printf("%d ", i);
        }

    return 0;
}


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