#include <bits/stdc++.h>
using namespace std;
int n, m;
int f[1005];
int a[300005][15];
void mo() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
}
void nhap() {
  cin >> n >> m;
  for (int i = 1; i <= n; i++)
    for (int j = 1; j <= m; j++) {
      cin >> a[i][j];
    }
}
pair<int, int> check(int g) {
  for (int i = 0; i < (1 << m); i++) {
    f[i] = 0;
  }
  f[0] = n + 1;
  for (int i = 1; i <= n; i++) {
    int state = 0;
    for (int j = 1; j <= m; j++) {
      if (a[i][j] >= g) state = state ^ (1 << (j - 1));
    }
    f[state] = i;
  }
  for (int state = 0; state < (1 << m); state++) {
    if (f[state] != 0)
      for (int prestate = state; prestate; prestate = (prestate - 1) & state) {
        f[prestate] = f[state];
      }
  }
  for (int state = 0; state < (1 << m); state++) {
    int prestate = state ^ ((1 << m) - 1);
    if (f[state] != 0 && f[prestate] != 0) {
      return pair<int, int>(f[state], f[prestate]);
    }
  }
  return pair<int, int>(-1, -1);
}
void xuli() {
  int l = 0;
  int r = round(1e9);
  pair<int, int> res;
  while (l <= r) {
    int mid = (l + r) >> 1;
    pair<int, int> tmp = check(mid);
    if (tmp.first != -1) {
      res = tmp;
      l = mid + 1;
    } else
      r = mid - 1;
  }
  if (res.first == n + 1) res.first = res.second;
  if (res.second == n + 1) res.second = res.first;
  cout << res.first << " " << res.second;
}
int main() {
  mo();
  nhap();
  xuli();
}
