public static string ToJson(SparseIntVectu32 vector) { var sb = new StringBuilder(); sb.Append("{"); sb.Append($"\"size\":{vector.size()},"); sb.Append("\"nonzero\":{"); sb.Append(string.Join(",", vector.GetNonzero().Select(n => $"{n.first}:{n.second}"))); sb.Append("}}"); return sb.ToString(); }
public static int Count(this SparseIntVectu32 v) => (int)v.size();