#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, t, sum = 0;
  char s[10];
  scanf("%d", &n);
  bool k = 1;
  while (n--) {
    scanf("%d%s", &t, s);
    if ((sum == 0 && s[0] != 'S') || (sum == 20000 && s[0] != 'N')) k = 0;
    if (s[0] == 'N')
      sum -= t;
    else if (s[0] == 'S')
      sum += t;
    if (sum < 0 || sum > 20000) k = 0;
  }
  if (sum == 0 && k)
    printf("YES\n");
  else
    printf("NO\n");
  return 0;
}
