Schematic diagrams of formation scenarios of unevolved Li-rich stars considered in this study. In the AGB scenario shown in the leftmost column, the pollution occurs from a giant star to the currently observed star. The donor star is now expected to be a white dwarf. The remaining columns show scenarios in which pollution from a classical nova is considered. Depending on whether the currently observed star was the donor or not, we further divided the nova scenario into cases 1 and 2. The final state of the nova scenario can be a single, binary, or triple-star system.