#include <bits/stdc++.h>
using namespace std;
template <typename T, typename T1>
T amax(T &a, T1 b) {
  if (b > a) a = b;
  return a;
}
template <typename T, typename T1>
T amin(T &a, T1 b) {
  if (b < a) a = b;
  return a;
}
bool isPrime(long long x) {
  if (x == 1) return false;
  for (long long i = 2; i * i <= x; i++) {
    if (x % i == 0) {
      return false;
    }
  }
  return true;
}
bool isPowerOfTwo(long long n) {
  if (n == 0) return false;
  return (ceil(log2(n)) == floor(log2(n)));
}
long long gcdByBit(long long a, long long b) {
  if (!a || !b) return a | b;
  unsigned shift = __builtin_ctz(a | b);
  a >>= __builtin_ctzl(a);
  do {
    b >>= __builtin_ctzl(b);
    if (a > b) {
      swap(a, b);
    }
    b -= a;
  } while (b);
  return a << shift;
}
long long powerMod(long long n, long long p) {
  long long res = 1;
  while (p) {
    if (p % 2 == 0) {
      n = n * 1ll * n % 1000000007;
      p /= 2;
    } else {
      res = res * 1ll * n % 1000000007;
      p--;
    }
  }
  return res;
}
long long powerMod2(long long b, long long p, long long m) {
  if (p == 0) return 1;
  return (b * powerMod2(b, p - 1, m) % m) % m;
}
long long fact(long long n) {
  long long res = 1;
  for (long long i = 1; i <= n; i++) {
    res = res * 1ll * i % 1000000007;
  }
  return res;
}
long long nCr(long long n, long long r) {
  return fact(n) * 1ll * powerMod(fact(r), 1000000007 - 2) % 1000000007 * 1ll *
         powerMod(fact(n - r), 1000000007 - 2) % 1000000007;
}
long long arr[300005];
long long ans[300005];
long long parent(long long x) {
  if (arr[x] != x) arr[x] = parent(arr[x]);
  return arr[x];
}
void Chaliye_Shuru_Karte_Hai() {
  for (long long i = 0; i < 300005; i++) arr[i] = i;
  long long n, m;
  cin >> n >> m;
  for (long long i = 0; i < m; i++) {
    long long a, b, c;
    cin >> a >> b >> c;
    for (long long j = parent(a); j <= b; j = parent(j + 1)) {
      if (j != c) ans[j] = c, arr[j] = j + 1;
    }
  }
  for (long long i = 1; i < n + 1; i++) cout << ans[i] << " ";
}
signed main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long tc = 1;
  while (tc--) {
    Chaliye_Shuru_Karte_Hai();
  }
  return 0;
}
