HIJ>PVG,(2hr25min stop), PVG>KMG, (19h55min stop), KMG>KTM

Hello, I am travelling from Hiroshima International airport to Kathmandu airport. But I have two stops at PVG and KMG with 2 hr 25 min and 19hr 55min respectively. Do I need transit visa during this travel. Does the 24 hr transit visa count only transit hours or does it also include flight as well as transit time period?