#include <bits/stdc++.h>
using namespace std;
const int MAXN = 2e5 + 10;
int n, m, s, d;
vector<pair<int, int>> vec, sec;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cin >> n >> m >> s >> d;
  for (int i = 0; i < n; i++) {
    int x;
    cin >> x;
    vec.push_back({x, x + 1});
  }
  sort(vec.begin(), vec.end());
  if (vec[0].first <= s) {
    cout << "IMPOSSIBLE\n";
    return 0;
  }
  for (int i = 0; i < vec.size(); i++) {
    if (sec.empty() || vec[i].first - sec.back().second > s)
      sec.push_back(vec[i]);
    else
      sec.back().second = vec[i].second;
  }
  for (auto v : sec)
    if (v.second - v.first >= d) {
      cout << "IMPOSSIBLE\n";
      return 0;
    }
  int cur = 0;
  for (auto v : sec) {
    if (cur + 1 < v.first) cout << "RUN " << v.first - cur - 1 << "\n";
    cout << "JUMP " << v.second - v.first + 1 << "\n";
    cur = v.second;
  }
  if (cur < m) cout << "RUN " << m - cur << "\n";
  return 0;
}
