#include <bits/stdc++.h>
using namespace std;
int const N = 1000 + 10;
char ch[N];
int len, lA, la, i;
int main() {
  while (cin >> ch[len]) len++;
  for (i = 0; i < len; i++)
    if (ch[i] >= 'A' && ch[i] <= 'Z')
      lA++;
    else if (ch[i] >= 'a' && ch[i] <= 'z')
      la++;
  if (lA > la) {
    for (i = 0; i < len; i++)
      if (ch[i] >= 'a' && ch[i] <= 'z') ch[i] -= 32;
  } else {
    for (i = 0; i < len; i++)
      if (ch[i] >= 'A' && ch[i] <= 'Z') ch[i] += 32;
  }
  cout << ch << endl;
  return 0;
}
