#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
//#include<bits/extc++.h>
//__gnu_pbds
struct seg{
int l;
int r;
int ind;
};
vector<seg> arr;
vector<bool> taken;
vector<int> frontans;
vector<int> backans;
vector<int> frontord;
vector<int> backord;
int n;
void rebuilt(){
for(int i=0;i<n;i++){
frontans[i]=0;
backans[i]=0;
}
int prev = -1;
for(int i=0;i<n;i++){
if(arr[frontord[i]].l<prev || taken[frontord[i]]){
if(i) frontans[i] = frontans[i-1];
else frontans[i]=0;
}else{
if(i) frontans[i] = frontans[i-1]+1;
else frontans[i]=1;
prev = arr[frontord[i]].r;
}
}
prev = 1e9;
for(int i=0;i<n;i++){
if(arr[backord[i]].r>prev || taken[backord[i]]) {
if(i) backans[i] = backans[i-1];
else backans[i]=0;
}else{
if(i) backans[i] = backans[i-1]+1;
else backans[i]=1;
prev = arr[backord[i]].l;
}
}
}
int main(){
ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0);
int K;cin>>n>>K;
arr.resize(n+1);
taken.resize(n+1);
frontans.resize(n+1);
backans.resize(n+1);
for(int i=1;i<=n;i++){
int a,b;cin>>a>>b;
arr[i].l = a;
arr[i].r = b;
arr[i].ind = i;
}
for(int i=1;i<=n;i++) frontord.push_back(i);
for(int i=1;i<=n;i++) backord.push_back(i);
sort(frontord.begin(),frontord.end(),[&](const int &a,const int &b){return arr[a].r<arr[b].r;});
sort(backord.begin(),backord.end(),[&](const int &a,const int &b){return arr[a].l>arr[b].l;});
rebuilt();
for(int i=1;i<=n;i++){
if(taken[i]) continue;
/*
cout<<i<<":"<<"\n";
for(int i=0;i<n;i++){
cout<<frontans[i]<<" ";
}
cout<<"\n";
for(int i=0;i<n;i++){
cout<<backans[i]<<" ";
}
cout<<"\n";
//if(taken[i]) continue;
*/
if(K==0) return 0;
int total = 1;
int l = -1;int r = n;
while(r-l>1){
int mid = (l+r)/2;
if(arr[frontord[mid]].r<=arr[i].l) l = mid;
else r = mid;
}
total+=(l<0)?(0):frontans[l];
l = -1;r = n;
while(r-l>1){
int mid = (l+r)/2;
if(arr[backord[mid]].l>=arr[i].r) l = mid;
else r = mid;
}
total+=(l<0)?(0):backans[l];
if(total>=K){
cout<<i<<"\n";
K--;
for(int p=1;p<=n;p++){
if(max(arr[p].l,arr[i].l)<min(arr[p].r,arr[i].r)) taken[p]=1;
}
}else{
taken[i]=1;
}
rebuilt();
}
if(K) cout<<-1<<"\n";
return 0;
}
