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#include <cstdio>
#include <set>
#include <vector>
#include <deque>


typedef unsigned int smallnum;
// typedef unsigned char mininum;
typedef std::set<smallnum> smallset;
typedef std::deque<smallnum> smallqueue;


class node {
public:
  smallnum number;
  int tree_parent;

  smallset incoming_love;
  smallset outgoing_love;
  smallset incoming_hate;
  smallset outgoing_hate;
};

void debug_print_set(const smallset s) {
  printf("set(");

  for (smallset::iterator iter = s.begin(); iter != s.end(); iter++) {
    printf("%u,", *iter);
  }

  printf(")\n");
}


int main() {
  // Step 1 - Get data
  smallnum n, m;
  scanf("%u %u\n", &n, &m);

  // Set up nodes structure
  std::vector<node> nodes(n);
  for (smallnum i = 0; i < n; i++) {
    nodes[i].number = i;
    nodes[i].tree_parent = -2;
  }

  for (smallnum i = 0; i < m; i++) {
    smallnum a, b;
    char c;
    scanf("%u %u %c\n", &a, &b, &c);

    // We readress nodes to k - 1, so that they match array indices
    switch(c) {
    case 'T':
      nodes[a-1].outgoing_love.insert(b-1);
      nodes[b-1].incoming_love.insert(a-1);
      break;
    case 'N':
      nodes[a-1].incoming_hate.insert(b-1);
      nodes[b-1].outgoing_hate.insert(a-1);
      break;
    }
  }
  // Step 2 - select CEO
  int ceo_idx = -1;

  for (smallnum i = 0; i < n; i++) {
    node& n = nodes[i];

    if ((n.outgoing_love.size() + n.outgoing_hate.size()) == 0) {
      ceo_idx = i;
      break;
    }
  }

  if (ceo_idx == -1) {
    // Exit if no CEO material exists
    printf("NIE\n");
    return 0;
  }

  // Special CEO parent - no parent
  node& ceo_node = nodes[ceo_idx];
  ceo_node.tree_parent = -1;
  // printf("DEBUG - CEO EXISTS = %d\n", ceo_idx);

  // Step 2.5 - we need to delete love to CEO
  for (smallset::iterator i = ceo_node.incoming_love.begin(); i != ceo_node.incoming_love.end(); i++) {
    node& found_node = nodes[*i];
    found_node.outgoing_love.erase(ceo_idx);
  }

  // Step 3 - put good nodes in the queue
  smallqueue nodes_to_process; // Nodes that we can process

  for (smallnum node_idx = 0; node_idx < n; node_idx++) {
    node& current_node = nodes[node_idx];

    if (current_node.tree_parent != -2) {
      // Node already done, ignore -- Just in the CEO case so far
      continue;
    }


    // Node has incoming love, ignore for now
    if (current_node.incoming_love.size() > 0) {
      continue;
    }

    // Node has outgoing love and no incoming love, add it to the queue
    // printf("DEBUG - PUSH TO QUEUE %u\n", node_idx);
    nodes_to_process.push_back(node_idx);
  }

  // Step 4 - main processing
  while (!nodes_to_process.empty()) {
    smallnum node_idx = nodes_to_process.front();
    nodes_to_process.pop_front();

    // printf("DEBUG - QUEUE PROCESSING %u\n", node_idx);

    // Step 3.1 - select the node to process now
    // We process nodes from the "bottom" so only nodes with no incoming love.
    // Nodes with incoming love, will be processed in their turn.
    node& current_node = nodes[node_idx];

    // Just in case, shouldn't happen
    if (current_node.tree_parent != -2) {
      // Node already done, ignore
      continue;
    }

    // No outgoing love, attach to CEO
    if (current_node.outgoing_love.size() == 0) {
      current_node.tree_parent = ceo_idx;
      // printf("DEBUG - ATTACH TO CEO %u\n", node_idx);
      continue;
    }

    // We have a node with outgoing love.
    // What we need to do is select the node from outgoing love set,
    // That is not reachable by any edge distance from this set

    // Before BFS - new bfs distances, all initialized to -1
    std::vector<int> bfs_distance(n, -1);
    // BFS DISTANCE - -1 not visited, not put in the queue
    // BFS DISTANCE - 0 - put in the queue, reached without going through hate branches
    // BFS DISTANCE - 1 - put in the queue, reached with going through hate branches once
    // BFS DISTANCE - 2 - processed and done
    bfs_distance[node_idx] = 0; // Probably doesn't matter what we put here

    smallset& original_set = current_node.outgoing_love; // just an alias, no copy
    smallset candidate_set = current_node.outgoing_love; // set of candidates that are good, a copy

    // Remove personal hate from the candidate set
    for (smallset::iterator iter = current_node.incoming_hate.begin(); iter != current_node.incoming_hate.end(); iter++) {
      candidate_set.erase(*iter); // Generally if that happens, we should just quit
    }

    // printf("DEBUG - outgoing love");
    // debug_print_set(current_node.outgoing_love);
    // printf("DEBUG - incoming hate");
    // debug_print_set(current_node.incoming_hate);

    std::deque<smallnum> bfs_queue;

    // Push original set elements to the queue
    for (smallset::iterator iter = original_set.begin(); iter != original_set.end(); iter++) {
      bfs_distance[*iter] = 0;
      bfs_queue.push_back(*iter);
    }

    while (!bfs_queue.empty()) {
      // printf("DEBUG  - candidate set\n");
      // debug_print_set(candidate_set);

      smallnum bfs_candidate = bfs_queue.front();
      bfs_queue.pop_front();

      smallnum candidate_distance = bfs_distance[bfs_candidate];

      if (candidate_distance >= 2) {
        // Guy already processed
        continue;
      }

      // printf("BFS - process %u\n", bfs_candidate);

      node& visited_node = nodes[bfs_candidate];

      // printf("BFS candidate - outgoing love\n");
      // debug_print_set(visited_node.outgoing_love);

      for(smallset::iterator iter = visited_node.outgoing_love.begin(); iter != visited_node.outgoing_love.end(); iter++) {
        candidate_set.erase(*iter);

        int new_item_distance = bfs_distance[*iter];

        if (new_item_distance == -1) {
          bfs_distance[*iter] = candidate_distance;

          if (candidate_distance == 0) {
            bfs_queue.push_front(*iter);
          } else {
            bfs_queue.push_back(*iter);
          }
        }

        // DO NOTHING
        // if (new_item_distance == 0) {}
        // if (new_item_distance == 2) {}

        if (new_item_distance == 1 && candidate_distance == 0) {
          bfs_distance[*iter] = candidate_distance;
          bfs_queue.push_front(*iter);
        }
      }

      // printf("BFS candidate - outgoing hate\n");
      // debug_print_set(visited_node.outgoing_hate);

      // If candidate distance is 1, then don't do that part at all
      if (candidate_distance < 1) {
        for(smallset::iterator iter = visited_node.outgoing_hate.begin(); iter != visited_node.outgoing_hate.end(); iter++) {
          candidate_set.erase(*iter);

          int new_item_distance = bfs_distance[*iter];

          if (new_item_distance == -1) {
            bfs_distance[*iter] = 1;
            bfs_queue.push_back(*iter);
          }
        }
      }

      bfs_distance[bfs_candidate] = 2;
    }

    // printf("XXX");
    // printf("DEBUG  - candidate set\n");
    // debug_print_set(candidate_set);

    if (candidate_set.empty()) {
      // printf("DEBUG - NO SOLUTION FOUND in BFS\n");
      printf("NIE\n");
      return 0;
    }

    smallnum parent_idx = *candidate_set.begin();
    // printf("DEBUG - PARENT SET TO = %u\n", parent_idx);

    current_node.tree_parent = parent_idx;

    // Update parent love and hate
    node& parent = nodes[parent_idx];

    parent.incoming_love.erase(node_idx);

    // We overwrite the arrows
    // parent.outgoing_love.insert(current_node.outgoing_love.begin(), current_node.outgoing_love.end());
    // parent.outgoing_love.erase(parent_idx); // in case it was put there

    for (smallset::iterator iter = current_node.outgoing_love.begin(); iter != current_node.outgoing_love.end(); iter++) {
      if (*iter != parent_idx) {
        node& other_node = nodes[*iter];

        parent.outgoing_love.insert(*iter);
        other_node.incoming_love.erase(node_idx);
        other_node.incoming_love.insert(parent_idx);
      }
    }

    for (smallset::iterator iter = current_node.incoming_hate.begin(); iter != current_node.incoming_hate.end(); iter++) {
      if (*iter != parent_idx) {
        node& other_node = nodes[*iter];

        parent.incoming_hate.insert(*iter);
        other_node.outgoing_hate.erase(node_idx);
        other_node.outgoing_hate.insert(parent_idx);
      }
    }

    // parent.incoming_hate.insert(current_node.incoming_hate.begin(), current_node.incoming_hate.end());
    // parent.incoming_hate.erase(parent_idx); // in case it was put there

    if ((parent.tree_parent == -2) && (parent.incoming_love.size() == 0)) {
      // printf("DEBUG - PUSH TO QUEUE %u\n", parent_idx);
      nodes_to_process.push_back(parent_idx);
    }
  }

  for (smallnum node_idx = 0; node_idx < n; node_idx++) {
    if (nodes[node_idx].tree_parent == -2) {
      // Some nodes were not allocated, probably because of cycle in love
      // printf("DEBUG - NO SOLUTION FOUND\n");
      printf("NIE\n");
      return 0;
    }
  }

  // printf("================ SOLUTION - TAKTAKTAK ===========\n");

  for(smallnum node_idx = 0; node_idx < n; node_idx++) {
    printf("%u\n", nodes[node_idx].tree_parent + 1);
  }

  return 0;
}