【leetcode】Valid Parentheses

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

The brackets must close in the correct order, "()" and "()[]{}" are all valid but "(]" and "([)]" are not.

bool isValid(char *s) {
  const int size = 10000;
  char stack[size];
  int p = 0;

  for (; *s != '\0'; ++s) {
    switch (*s) {
    case ')':
      if (p == 0 || stack[p - 1] != '(') {
        return false;
      }
      --p;
      break;

    case ']':
      if (p == 0 || stack[p - 1] != '[') {
        return false;
      }
      --p;
      break;

    case '}':
      if (p == 0 || stack[p - 1] != '{') {
        return false;
      }
      --p;
      break;

    default:
      stack[p++] = *s;
    } // switch
  }

  return p == 0;
}