#include <bits/stdc++.h>
using namespace std;
int i, j, n, m, p, k, ans;
char s[2005];
int main() {
  scanf("%d", &n);
  k = 0;
  for (i = 0; i < n; i++) {
    scanf("%d", &m);
    getchar();
    gets(s);
    if (s[0] == 'S' && k + m > 20000) {
      printf("NO\n");
      return 0;
    }
    if (s[0] == 'N' && k - m < 0) {
      printf("NO\n");
      return 0;
    }
    if (s[0] != 'S' && k == 0) {
      printf("NO\n");
      return 0;
    }
    if (s[0] != 'N' && k == 20000) {
      printf("NO\n");
      return 0;
    }
    if (s[0] == 'S') k += m;
    if (s[0] == 'N') k -= m;
  }
  if (k != 0) {
    printf("NO\n");
    return 0;
  }
  printf("YES\n");
  return 0;
}
