#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, res = 0;
  cin >> n;
  while (n--) {
    int a;
    string s;
    cin >> a >> s;
    if (s[0] == 'N') {
      if (res - a < 0)
        return cout << "NO\n", 0;
      else
        res -= a;
    } else if (s[0] == 'S') {
      if (res + a > 2e4)
        return cout << "NO\n", 0;
      else
        res += a;
    } else if (!res or res == 2e4)
      return cout << "NO\n", 0;
  }
  return cout << (!res ? "YES\n" : "NO\n"), 0;
}
