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#include <cstdio>
#include <algorithm>
#include <vector>
#include <cstdlib>
using namespace std;
const int debug = 0;

struct person {
  vector<int> up /* bosses */, down, other /* up or down */, notup /* N */;
  int s;  // original up.size()
  int k;
  bool vis;
  int father, depth;
};

void fail() {
  printf("NIE\n");
  exit(0);
}

person p[1000];
int n;
char dep[1000][1000];
// dep[i][j] = 1 (j is a boss), -1 (i is a boss), -2 (j is not a boss), 0 (unknown), 2 (one of them is a boss)

#define print do { \
  printf("---------- PRINT %d -----------------\n", __LINE__); \
  for (int ii = 0; ii < n; ++ii) { \
    for (int jj = 0; jj < n; ++jj) \
      printf("%d\t", dep[ii][jj]); \
    printf("\n"); \
  } \
  printf("*****************************************\n"); \
} while(0)

vector<pair<int, int> > new_boss;  // (a, b) - a is a boss

void add_boss(int a, int b, bool add) {
  if (debug >= 1)
    printf("xxx add boss %d %d    (%d) xxx\n", a, b, add);
  dep[a][b] = -1;
  if (dep[b][a] < 0)
    fail();
  dep[b][a] = 1;
  p[a].down.push_back(b);
  p[b].up.push_back(a);
  if (add)
    new_boss.push_back(make_pair(a, b));
}

void fix(int a, int b) {  // one of them is the boss
  if (debug >= 3)
    printf("fix: %d %d\n", a, b);
  if (dep[a][b] == 1 || dep[a][b] == -1)
    return;
  if (dep[a][b] == -2) {  // a is a boss
    add_boss(a, b, 1);
  }
  if (dep[b][a] == -2) {  // b is a boss
    add_boss(b, a, 1);
  }
  if (dep[a][b] == 0 && dep[b][a] == 0) {
    dep[a][b] = dep[b][a] = 2;
    p[a].other.push_back(b);
    p[b].other.push_back(a);
  }
}

// dep[i][j] = 1 (j is a boss), -1 (i is a boss), -2 (j is not a boss), 0 (unknown), 2 (one of them is a boss)
bool comp(int a, int b) {
  if (dep[a][b] == -1)  // a is the boss
    return 1;
  else if (dep[a][b] != 1)
    return p[a].other.size() + p[a].down.size() > p[b].other.size() + p[b].down.size();
  else 
    return 0;
}

bool can_be_boss(int b) {
  bool ok = true;
  for (int i = 0; i < n; ++i)
    if (dep[i][b] < 0) {
      ok = false;
      break;
    }
  return ok;
}

int main() {
  int k;
  scanf("%d %d ", &n, &k);
  while (k--) {
    int x, y;
    char c;
    scanf("%d %d %c", &x, &y, &c);
    --x;
    --y;
    if (debug >= 3)
      printf("%d %d %c\n", x, y, c);
    if (c == 'T') {
      p[x].up.push_back(y);
      p[y].down.push_back(x);
      dep[x][y] = 1;
      dep[y][x] = -1;
    }
    else {
      p[x].notup.push_back(y);
      dep[x][y] = -2;
    }
  }
  
  vector<int> queue;
  int counter = 0;
  int id[n];
  for (int i = 0; i < n; ++i) {
    p[i].k = p[i].s = p[i].up.size();
    if (p[i].k == 0)
      queue.push_back(i);
  }
  if (debug >= 3)
    print;
  //topo order: from the sink
  while (!queue.empty()) {  // update up and down; time = O(n * m)
    int x = queue.back();
  if (debug >= 3)
      printf("x = %d\n", x);
    ++counter;
    id[n-counter] = x;
    queue.pop_back();
    for (vector<int>::iterator i = p[x].down.begin(); i != p[x].down.end(); ++i) {
      if (!(--p[*i].k)) {
        queue.push_back(*i);
      }
    }
    int s = p[x].up.size();
    for (int i = 0; i < s; ++i) {  // total iterations: O(m)
      int y = p[x].up[i];
      for (vector<int>::iterator j = p[y].up.begin(); j != p[y].up.end(); ++j) {
// dep[i][j] = 1 (j is a boss), -1 (i is a boss), -2 (j is not a boss), 0 (unknown), 2 (one of them is a boss)
        if (dep[x][*j] < 0 || dep[*j][x] == 1)
          fail();
        else if (dep[x][*j] != 1) {
          dep[x][*j] = 1;
          dep[*j][x] = -1;
          p[x].up.push_back(*j);
          p[*j].down.push_back(x);
        }
      }
    }
  }
  if (counter != n)
    fail();
  if (debug >= 3)
    print;

  //topo order: from the source
  for (int i = 0; i < n; ++i) {  // update notup; time = O(n * m)
    int x = id[i];
    for (int j = 0; j < p[x].s; ++j) {
      int y = p[x].up[j];
      for (vector<int>::iterator vit = p[x].notup.begin(); vit != p[x].notup.end(); ++vit) {
// dep[i][j] = 1 (j is a boss), -1 (i is a boss), -2 (j is not a boss), 0 (unknown), 2 (one of them is a boss)
        if (dep[y][*vit] == 1)
          fail();
        else if (dep[y][*vit] == 0) {
          dep[y][*vit] = -2;
          p[y].notup.push_back(*vit);
        }
      }
    }
  } 
  if (debug >= 3)
    print;

  bool new_noup = false;
  do {
    new_noup = false;
    while (!new_boss.empty()) { // TODO
      int x = new_boss.back().first;  // x is a new boss of y
      int y = new_boss.back().second;
      new_boss.pop_back();
      if (debug >= 3)
        printf("wybrano %d %d <<<<<<<<<<<\n", x, y);
      int z = x;
      for (int i = -1; i < (int) p[x].up.size(); ++i) {
        if (i >= 0)
          z = p[x].up[i];
        int z2 = y;
        for (int j = -1; j < (int) p[y].down.size(); ++j) {
          if (j >= 0)
            z2 = p[y].down[j];
          if (debug >= 3)
            printf(">>>>>> z2 = %d, z = %d\n", z2, z);
          if (dep[z2][z] != 1)
            add_boss(z, z2, 0);
        }
      }
      for (unsigned i = 0; i < p[y].notup.size(); ++i) {
        z = p[y].notup[i];
        int z2 = x;
        for (int j = -1; j < (int) p[x].up.size(); ++j) {
          if (j >= 0)
            z2 = p[x].up[j];
          if (dep[z2][z] == 2) {
            add_boss(z2, z, 0);
          }
          else if (dep[z2][z] == 1)
            fail();
          else if (dep[z2][z] == 0) {
            dep[z2][z] = -2;
            new_noup = true;
          }
        }
      }
    }
    for (int i = 0; i < n; ++i)
      p[i].vis = false;
  //topo order: from the source
    for (int i = 0; i < n; ++i) {  // fix(a, b)
      int x = id[i];
      if (p[x].vis)
        continue;
  if (debug >= 3)
      printf(" @@@ inside @@@ x = %d\n", x);
      p[x].vis = true;
      int size = p[x].up.size();
      for (int a = 0; a < size; ++a) {
        p[p[x].up[a]].vis = true;
        for (int b = a+1; b < size; ++b) {
          fix(p[x].up[a], p[x].up[b]);
        }
      }
    }
    if (debug >= 3)
      print;
    if (new_boss.empty()) {
      for (int i = 0; i < n; ++i) {
        if (!new_boss.empty())
          break;
        for (int j = 0; j < n; ++j) {
          if (!new_boss.empty())
            break;
          if (dep[i][j] == 2) {
            if (debug >= 1)
              printf("random boss:\n");
            if (can_be_boss(i))
              add_boss(i, j, 1);
            else
              add_boss(j, i, 1);
          }
        }
      }
    }
  } while (!new_boss.empty());

  //find boss of all the bosses
  int b;
  for (b = 0; b < n; ++b) {
    if (can_be_boss(b))
      break;
  }
  if (b >= n)
    fail();
  if (debug >= 3)
    printf("b = %d\n", b + 1);
  for (int i = 0; i < n; ++i) {
    if (dep[i][b] != 1) {
      dep[i][b] = 1;
      dep[b][i] = -1;
      p[i].up.push_back(b);
      p[b].down.push_back(i);
    }
  }

  for (int i = 0; i < n; ++i) {  // clean p.other at the end
    unsigned j = 0;
    while (j < p[i].other.size()) {
      int y = p[i].other[j];
      if (dep[i][y] != 2) {
        p[i].other[j] = p[i].other[p[i].other.size()-1];
        p[i].other.pop_back();
      }
      else
        ++j;
    }
  }
  if (debug >= 3)
    print;

  sort(id, id+n, comp);
  if (b != id[0]) {
    printf("ERROR!\n");
    fail();
  }

  if (debug >= 3) {
    printf("id:\n");
    for (int i = 0; i < n; ++i) {
      printf("%d ", id[i] + 1);
    }
    printf("\n");
  }

  p[b].father = -1;
  p[b].depth = 0;
  for (int i = 1; i < n; ++i) {
    int x = id[i];
    p[x].father = b;
    for (unsigned j = 0; j < p[x].up.size(); ++j) {
      int y = p[x].up[j];
      if (p[y].depth + 1 > p[x].depth) {
        p[x].depth = p[y].depth + 1;
        p[x].father = y;
      }
    }
    if (debug >= 3)
      printf("%d: father: %d\n", x+1, p[x].father+1);
  }

  //last check
  for (int i = 0; i < n; ++i) {
    int j = i;
    while (j != b) {
      j = p[j].father;
      if (dep[i][j] < 0) {
        fail();
      }
      dep[i][j] = 0;
    }
    for (j = 0; j < n; ++j)
      if (dep[i][j] == 1) {
        fail();
      }
  }

//  printf("TAK\n");


  if (debug == 0) {
    for (int i = 0; i < n; ++i)
      printf("%d\n", p[i].father + 1);
  }


  return 0;
}