#include <bits/stdc++.h>
using namespace std;
const int maxn = 40;
long long int dp[maxn][maxn], P[maxn], par[maxn][maxn];
string s;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  P[0] = 1;
  for (int i = 1; i < maxn; i++) P[i] = P[i - 1] * 10;
  cin >> s >> s;
  for (int i = ((int)(s).size()) - 1; i >= 0; i--) {
    for (int j = 0; j <= ((int)(s).size()) - i; j++) {
      long long int pnt1, pnt2;
      if (j == 0)
        dp[i][j] = dp[i + 1][j] + (s[i] - '0') * P[((int)(s).size()) - i - 1],
        par[i][j] = j;
      else if (j == ((int)(s).size()) - i)
        dp[i][j] = dp[i + 1][j - 1] + (s[i] - '0') * P[j - 1],
        par[i][j] = j - 1;
      else if ((pnt1 = dp[i + 1][j - 1] + (s[i] - '0') * P[j - 1]) >
               (pnt2 = dp[i + 1][j] +
                       (s[i] - '0') * P[((int)(s).size()) - i - j - 1]))
        dp[i][j] = pnt1, par[i][j] = j - 1;
      else
        dp[i][j] = pnt2, par[i][j] = j;
    }
  }
  int row = 0, col = ((int)(s).size()) / 2;
  while (row < ((int)(s).size())) {
    if (par[row][col] == col)
      cout << 'H';
    else
      cout << 'M';
    col = par[row][col];
    row++;
  }
  return 0;
}
