What bus is Hengyang high-speed train to Changning?

It is a high-speed train with the prefix G and D. The G-prefix high-speed train refers to a high-speed train with a speed of more than 250 kilometers per hour, and the D-prefix high-speed train refers to a high-speed train with a speed of more than 200 kilometers per hour and less than 250 kilometers per hour ... Although the train types may be slightly different, they are all advanced high-speed trains with high speed and high comfort, which is a more convenient choice for travel.