using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace HeuristicLab.Algorithms.DataAnalysis.SymRegGrammarEnumeration.GrammarEnumeration {
  public class SymbolString : List<Symbol> {

    public SymbolString(IEnumerable<Symbol> symbols) : base(symbols) { }

    public bool IsSentence() {
      return this.All(sym => sym is TerminalSymbol);
    }

    public int[] GetNonterminalSymbolIndexes() {
      return Enumerable.Range(0, Count)
        .Where(i => this[i] is NonterminalSymbol)
        .ToArray();
    }

    public override string ToString()
    {
      return string.Join(" ", this);
    }
  }
}