#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int, int>
#define f first
#define s second
#define REP(i,n) for (int i = 0; i<n; ++i)
#define REP1(i,n) for (int i = 1; i<=n; ++i)
#define MX(a,b) a = max(a,b)
#define MN(a,b) a = min(a,b)
#define pb push_back
#define SZ(x) (int)(x).size()
#define ALL(x) (x).begin(), (x).end()
#ifdef BALBIT
#define bug(...) cerr<<"#"<<__LINE__<<": "<<#__VA_ARGS__<<"- ", _do(__VA_ARGS__)
template<typename T> void _do(T && x) {cerr<<x<<endl;}
template<typename T, typename ...S> void _do(T && x, S && ...y) {cerr<<x<<", "; _do(y...);}
#else
#define bug(...)
#endif // BALBIT
const int maxn = 6e3+5;
bool ban[maxn];
int ps[maxn];
pii v[maxn];
ll dp[maxn];
vector<int> upd[maxn];
int tryrem(int x) {
for (int j = v[x].f+1; j<=v[x].s; ++j) {
if (ban[j]) return -maxn;
}
for (int j = v[x].f+1; j<=v[x].s; ++j) {
ban[j] = 1;
}
for (int i = 1; i<maxn; ++i) {
ps[i] = ps[i-1] + ban[i];
}
ll re = 0;
for (int i = 1; i<maxn; ++i) {
dp[i] = 0;
MX(dp[i], dp[i-1]);
for (int l : upd[i]) {
if (ps[i] - ps[l]) continue;
MX(dp[i], dp[l] + 1);
}
MX(re, dp[i]);
}
for (int j = v[x].f+1; j<=v[x].s; ++j) {
ban[j] = 0;
}
return re;
}
signed main(){
ios::sync_with_stdio(0), cin.tie(0);
bug(1,2);
int n,k; cin>>n>>k;
vector<int> xpos;
REP(i,n) {
cin>>v[i].f>>v[i].s;
xpos.pb(v[i].f); xpos.pb(v[i].s);
}
sort(ALL(xpos));
xpos.resize(unique(ALL(xpos)) - xpos.begin());
REP(i, n) {
pii &p = v[i];
p.f = lower_bound(ALL(xpos), p.f) - xpos.begin();
p.s = lower_bound(ALL(xpos), p.s) - xpos.begin();
bug(p.f, p.s);
upd[p.s].pb(p.f);
}
vector<int> took;
for (int i = 0; i<n; ++i) {
if (tryrem(i) + 1 + SZ(took) >= k) {
// ok!
took.pb(i);
bug(i);
for (int j = v[i].f+1; j<=v[i].s; ++j) {
ban[j] = 1;
}
}else{
}
}
if (k <= SZ(took)) {
REP(i,k) cout<<took[i]+1<<endl;
}else{
cout<<-1<<endl;
}
}
