public void TestParsing19() {
var g = new Grammar(new List<Production>{
CFGParser.Production("<X_0> → <X_2> 'x2' 'x0' [89.380999392075935]"),
CFGParser.Production("<X_2> → <X_0> [54.4160114142187]"),
CFGParser.Production("<X_0> → 'x1' [73.603592962307658]"),
CFGParser.Production("<X_2> → 'x2' 'x2' 'x1' <X_2> [72.673047343116735]")
}, Nonterminal.Of("X_0"));
var sentences = new List<Sentence>();
sentences.Add(Sentence.FromWords("x1"));
ExecuteTest(g, sentences);
}