#include <bits/stdc++.h>
using namespace std;
int l[100100], r[100100], v[100100];
vector<int> Pos[300100], End[300100];
bool fl[300100];
int Max[300100 << 2];
int addv[300100 << 2];
int pos[300100 << 2];
int ans, ansP, ansE;
inline int left(int a) { return a << 1; }
inline int right(int a) { return a << 1 | 1; }
void push_up(int id) {
  if (Max[left(id)] > Max[right(id)]) {
    Max[id] = Max[left(id)];
    pos[id] = pos[left(id)];
  } else {
    Max[id] = Max[right(id)];
    pos[id] = pos[right(id)];
  }
}
void push_down(int id) {
  if (addv[id]) {
    Max[left(id)] += addv[id];
    Max[right(id)] += addv[id];
    addv[left(id)] += addv[id];
    addv[right(id)] += addv[id];
    addv[id] = 0;
  }
}
void build(int l, int r, int id) {
  Max[id] = 0;
  addv[id] = 0;
  if (l == r) {
    pos[id] = l;
    return;
  }
  int m = (l + r) >> 1;
  build(l, m, left(id));
  build(m + 1, r, right(id));
  push_up(id);
}
void Add(int L, int R, int v, int l, int r, int id) {
  if (L <= l && r <= R) {
    Max[id] += v;
    addv[id] += v;
    return;
  }
  push_down(id);
  int m = (l + r) >> 1;
  if (L <= m) Add(L, R, v, l, m, left(id));
  if (m < R) Add(L, R, v, m + 1, r, right(id));
  push_up(id);
}
int main() {
  int n;
  scanf("%d", &n);
  int tot = 0;
  for (int i = 1; i <= n; i++) {
    scanf("%d %d %d", l + i, v + i, r + i);
    Pos[v[i]].push_back(i);
    End[r[i]].push_back(i);
    fl[v[i]] = fl[r[i]] = 1;
    if (r[i] > tot) tot = r[i];
  }
  build(1, tot, 1);
  ans = 0;
  for (int i = 1; i <= tot; i++)
    if (fl[i]) {
      for (int j = 0; j < Pos[i].size(); j++) {
        int ii = Pos[i][j];
        Add(l[ii], v[ii], 1, 1, tot, 1);
      }
      if (Max[1] > ans) ans = Max[1], ansP = pos[1], ansE = i;
      for (int j = 0; j < End[i].size(); j++) {
        int ii = End[i][j];
        Add(l[ii], v[ii], -1, 1, tot, 1);
      }
    }
  printf("%d\n", ans);
  bool bf = 0;
  for (int i = 1; i <= n; i++)
    if (l[i] <= ansP && ansP <= v[i] && v[i] <= ansE && r[i] >= ansE) {
      if (bf) putchar(' ');
      printf("%d", i);
      bf = 1;
    }
  puts("");
}
