#include <bits/stdc++.h>
using namespace std;
int inf_int = 2e9;
long long inf_ll = 1e18;
const double pi = 3.1415926535898;
bool debug = 0;
const int MAXN = 3e5 + 100000;
int mod = 1e9 + 9;
int L[MAXN], R[MAXN];
bool com(pair<int, int> a, pair<int, int> b) {
  pair<int, int> x, y;
  if (a.second == 0) {
    x = {L[a.first], 0};
  } else {
    x = {R[a.first], 1};
  }
  if (b.second == 0) {
    y = {L[b.first], 0};
  } else {
    y = {R[b.first], 1};
  }
  return x < y;
}
void solve() {
  int n;
  cin >> n;
  int k;
  cin >> k;
  vector<pair<int, int> > a;
  for (int i = 0; i < n; ++i) {
    cin >> L[i] >> R[i];
    a.push_back({i, 0});
    a.push_back({i, 1});
  }
  sort(a.begin(), a.end(), com);
  set<pair<int, int> > s1, s2;
  int ans = 0;
  for (int i = 0; i < a.size(); ++i) {
    int ind = a[i].first;
    if (a[i].second == 0) {
      s2.insert({L[ind], ind});
    } else {
      if (s1.size() + s2.size() < k) {
      } else {
        while (s1.size() < k) {
          s1.insert(*s2.begin());
          s2.erase(s2.begin());
        }
        int l = max(s1.rbegin()->first, L[ind]);
        if (R[ind] - l + 1 >= ans) {
          ans = R[ind] - l + 1;
        }
      }
      s1.erase({L[ind], ind});
      s2.erase({L[ind], ind});
    }
  }
  if (ans == 0) {
    cout << ans << "\n";
    for (int i = 1; i <= k; ++i) {
      cout << i << " ";
    }
    return;
  } else {
    cout << ans << "\n";
    for (int i = 0; i < a.size(); ++i) {
      int ind = a[i].first;
      if (a[i].second == 0) {
        s2.insert({L[ind], ind});
      } else {
        if (s1.size() + s2.size() < k) {
        } else {
          while (s1.size() < k) {
            s1.insert(*s2.begin());
            s2.erase(s2.begin());
          }
          int l = max(s1.rbegin()->first, L[ind]);
          if (R[ind] - l + 1 == ans) {
            vector<int> res;
            res.push_back(ind);
            for (pair<int, int> x : s1) {
              if (res.size() == k) break;
              if (x.second != ind) {
                res.push_back(x.second);
              }
            }
            for (int v : res) {
              cout << v + 1 << " ";
            }
            return;
          }
        }
        s1.erase({L[ind], ind});
        s2.erase({L[ind], ind});
      }
    }
  }
}
int main() {
  if (!debug) {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
  }
  int t = 1;
  while (t--) solve();
  return 0;
}
