#include <bits/stdc++.h>
using namespace std;
inline int read() {
  int x = 0, y = 0;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') y = 1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9')
    x = (x << 1) + (x << 3) + (ch ^ 48), ch = getchar();
  return y ? -x : x;
}
template <typename T>
inline T read() {
  T x = 0;
  int y = 0;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') y = 1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9')
    x = (x << 1) + (x << 3) + (ch ^ 48), ch = getchar();
  return y ? -x : x;
}
char s[40];
long long pw[40] = {-0x3f3f3f3f, 1}, f[40][40];
bool g[40][40];
signed main() {
  int n = read();
  scanf("%s", s + 1);
  for (register int i = 2; i <= n; ++i) pw[i] = pw[i - 1] * 10;
  memset(f, ~0x3f, sizeof f);
  f[(n << 1) + 1][0] = 0;
  for (register int i = n << 1; i; --i)
    for (register int j = 0; j <= min((n << 1) - i + 1, n); ++j) {
      f[i][j] = max(f[i + 1][j - 1] + pw[j] * (s[i] - '0'),
                    f[i + 1][j] + pw[(n << 1) - i + 1 - j] * (s[i] - '0'));
      g[i][j] = f[i + 1][j - 1] + pw[j] * (s[i] - '0') >
                f[i + 1][j] + pw[(n << 1) - i + 1 - j] * (s[i] - '0');
    }
  for (register int i = 1, j = n; i <= n << 1; ++i)
    putchar(g[i][j] ? 'H' : 'M'), j -= g[i][j];
  putchar('\n');
}
