#include <bits/stdc++.h>
using namespace std;
int main() {
  int otv = 20000;
  int n, k;
  cin >> n;
  string s;
  bool b = true;
  for (int i = 0; i < n; i++) {
    cin >> k >> s;
    if (otv == 20000 && s != "South") {
      b = false;
    }
    if (otv == 0 && s != "North") {
      b = false;
    }
    if (s == "North") otv += k;
    if (s == "South") otv -= k;
    if (otv < 0 || otv > 20000) b = false;
  }
  if (otv == 20000 && b)
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
