#include<bits/stdc++.h>
using namespace std;
const int N=2e5+10, LG=18;
int n, k;
int l[N], r[N];
vector<int> vv[N];
int jump[LG][N];
int get(int l, int r){
int ans=0;
for (int k=LG-1; k>=0; --k){
if (jump[k][l]<=r){
ans+=1<<k;
l=jump[k][l];
}
}
return ans;
}
int32_t main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cin >> n >> k;
for (int i=1; i<=n; ++i) cin >> l[i] >> r[i];
for (int i=(1<<n)-1; i>=0; --i) if (__builtin_popcount(i)==k){
bool check=1;
for (int j=0; j<n; ++j) if (i>>(n-j-1)&1) for (int t=j+1; t<n; ++t) if (i>>(n-t-1)&1){
if (max(l[j+1], l[t+1])<min(r[j+1], r[t+1])){
check=0;
}
}
if (check){
for (int j=0; j<n; ++j) if (i>>(n-j-1)&1) cout << j+1 << '\n';
return 0;
}
}
cout << -1 << '\n';
return 0;
}
