#include <stdio.h>
#define N 100000
#define INF 0x3f3f3f3f
unsigned int Z = 12345;
int rand_() {
return (Z *= 3) >> 1;
}
int xx[N * 2], ii[N * 2], n;
void sort(int *ii, int l, int r) {
while (l < r) {
int i = l, j = l, k = r, i_ = ii[l + rand_() % (r - l)], tmp;
while (j < k)
if (xx[ii[j]] == xx[i_])
j++;
else if (xx[ii[j]] < xx[i_]) {
tmp = ii[i], ii[i] = ii[j], ii[j] = tmp;
i++, j++;
} else {
k--;
tmp = ii[j], ii[j] = ii[k], ii[k] = tmp;
}
sort(ii, l, i);
l = k;
}
}
int zz[N + 1], ii_[N + 1], ll[N + 1], rr[N + 1], u_, l_, r_;
int node(int i) {
static int _ = 1;
zz[_] = rand_(), ii_[_] = i;
return _++;
}
void split(int u, int i) {
int c;
if (u == 0) {
u_ = l_ = r_ = 0;
return;
}
c = xx[ii_[u] << 1 | 0] != xx[i << 1 | 0] ? xx[ii_[u] << 1 | 0] - xx[i << 1 | 0] : ii_[u] - i;
if (c < 0) {
split(rr[u], i);
rr[u] = l_, l_ = u;
} else if (c > 0) {
split(ll[u], i);
ll[u] = r_, r_ = u;
} else {
u_ = u, l_ = ll[u], r_ = rr[u];
ll[u] = rr[u] = 0;
}
}
int merge(int u, int v) {
if (u == 0)
return v;
if (v == 0)
return u;
if (zz[u] < zz[v]) {
rr[u] = merge(rr[u], v);
return u;
} else {
ll[v] = merge(u, ll[v]);
return v;
}
}
int tr_lower(int i) {
int u = u_, i_ = -1;
while (u)
if (xx[ii_[u] << 1 | 0] < xx[i << 1 | 0] || xx[ii_[u] << 1 | 0] == xx[i << 1 | 0] && ii_[u] < i)
i_ = ii_[u], u = rr[u];
else
u = ll[u];
return i_;
}
int tr_higher(int i) {
int u = u_, i_ = -1;
while (u)
if (xx[ii_[u] << 1 | 0] > xx[i << 1 | 0] || xx[ii_[u] << 1 | 0] == xx[i << 1 | 0] && ii_[u] > i)
i_ = ii_[u], u = ll[u];
else
u = rr[u];
return i_;
}
void tr_add(int i) {
split(u_, i);
u_ = merge(merge(l_, node(i)), r_);
}
int count(int l, int r) {
int i, i_, k;
k = 0;
for (i = 0; i < n * 2 && xx[i_ = ii[i]] <= r; i++)
if ((i_ & 1) == 1)
if (l <= xx[i_ ^ 1])
l = xx[i_], k++;
return k;
}
int main() {
int k, i, p, q, l, r, k_, k1, k1_;
scanf("%d%d", &n, &k);
for (i = 0; i < n * 2; i++)
scanf("%d", &xx[i]);
for (i = 0; i < n * 2; i++)
ii[i] = i;
sort(ii, 0, n * 2);
k1 = count(0, INF);
if (k1 < k) {
printf("-1\n");
return 0;
}
for (i = 0, k_ = 0; i < n && k_ < k; i++) {
p = tr_lower(i), q = tr_higher(i);
l = p == -1 ? 0 : xx[p << 1 | 1], r = q == -1 ? INF : xx[q << 1 | 0];
if (l <= xx[i << 1 | 0] && xx[i << 1 | 1] <= r) {
k1_ = k1 - count(l, r) + count(l, xx[i << 1 | 0]) + count(xx[i << 1 | 1], r);
if (k1_ + k_ + 1 >= k)
printf("%d\n", i + 1), tr_add(i), k1 = k1_, k_++;
}
}
return 0;
}
