CodeForces 361B Levko and Permutation

 1 #include<cstdio>
 2 #include<cstring>
 3 #include<algorithm>
 4 #include<iostream>
 5 #include<cstdlib>
 6 #include<string>
 7 #include<cmath>
 8 #include<vector>
 9 using namespace std;
10 const int maxn=1e5+7;
11 const double eps=1e-8;
12 const double pi=acos(-1);
13 #define ll long long
14 #define clc(a,b) memset(a,b,sizeof(a))
15 
16 int main()
17 {
18     int n,m;
19     scanf("%d%d",&n,&m);
20     if(n==m)
21     {
22         printf("-1\n");
23     }
24     else
25     {
26         printf("%d ",n-m);
27         for(int i=1;i<n-m;i++)
28             printf("%d ",i);
29         for(int i=n-m+1;i<=n;i++)
30             printf("%d ",i);
31     }
32     return 0;
33 }