Nifty is still in uptrend with the immediate support at 10500 levels. The trendline will be considered broken for the year 2018 only if it falls below 9000 level which was the double resistance level for nifty in the past.
Key levels to watch : 10500 , 1000
HPCL is below the 50 and 200 DMA and is in a downtrend with the resistance of 410 and support of 350.
You can use every opportunity to short when the stock reaches 400-410 and cover your position at 350-360.
You can go short on reliance until it reaches 880/875 which is a key support level.
At that time , reverse your position and go long on reliance around 870-875 with a stop loss of 850.