#include <iostream>
#include <cstring>

using namespace std;

int n;
long long x;
long long a[100];
bool z[100];

int p[] = {1009, 1013, 1019};
int dp[3][101][1100];

bool solve() {
  long long sum = 0;
  for (int i = 0; i < n; i++)
    sum += a[i];
  if (x > sum)
    return false;
  
  memset(dp, -1, sizeof(dp));
  for (int k = 0; k < 3; k++) {
    dp[k][0][0] = 0;
    for (int i = 0; i < n; i++) {
      for (int j = 0; j < p[k]; j++) {
        if (dp[k][i][j] == -1)
          continue;
        dp[k][i+1][j] = dp[k][i][j];
        dp[k][i+1][(j+a[i]) % p[k]] = i;
      }
    }
  }

  bool r = true;
  for (int k = 0; k < 3; k++)
    r &= dp[k][n][x % p[k]] != -1;

  if (r) {
    while (x > 0) {
      for (int i = 0; i < n; i++) {
        bool ck = true;
        for (int k = 0; k < 3; k++) {
          if (dp[k][i][(x-a[i]) % p[k]] == -1)
            ck = false;
        }
        if (ck) {
          x -= a[i];
          z[i] = true;
          break;
        }
      }
    }
  }
  
  return r;
}

int main(int argc, char *argv[])
{
  
  cin >> n >> x;
  for (int i = 0; i < n; i++)
    cin >> a[i];

  if (solve()) {
    string ret;
    for (int i = 0; i < n; i++) {
      if (z[i])
        ret += 'o';
      else
        ret += 'x';
    }
    cout << ret << endl;
  } else {
    cout << "No" << endl;
  }
  
  return 0;
}