Food Tip For 12773 SHM SC AC:
Before Boarding from SHM or SRC , get some snacks with you from Station or outside station. It will help a lot while journey. For Dinner , Get it from Cuttack or Bhubaneswar. Both these stations have Brilliant food options on stations and vendors sell food when this reaches on Platform. But Do take care that train halts for hardly 4-5 minutes (bcoz it always arrives delayed by 20-30 minutes) , so stay on your feet , otherwise you may miss your train. ;)
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Between VSKP-RJY , caterers do sell breakfast and Tea, but they are very less in amount. Get good breakfast from Rajahmundry Station.
Also to keep your tummy full , eat the snacks that you brought before boarding the train. (Now you will understand the reason why i asked you to purchase enough snacks chips/biscuits before boarding the train).
Now the BIGGEST TIP is Purchase your Lunch from Vijayawada Jn. Even if you don't feeling Hungry , still Purchase the food from Vijayawada station itself. Because between BZA and SC , there is absolutely no catering present onboard. Warangal halt also is just 2 min, so you can't get anything to eat. So purchase food from BZA station for pleasant journey between BZA-SC.
Food Tip for 12774 SC SHM AC:
Before Boarding , Buy some food for breakfast from Secunderabad itself. Purchase Lunch from Vijayawada station. Rajahmundry also has food option , but its bit costly and train also halts for just 2 minutes here. So purchase your Lunch from BZA itself. Now For night Dinner , Parcel from VSKP itself. Seriously telling , after VSKP , VZM & CHE do not have Good food options. And BBS - CTC station comes midnight , so pack food from VSKP and eat the same at night. Next day Great Breakfast (Hot Cheap tasty Poori-Bhaji) is present on Pf of Kharagpur. Train always halts for good 10 minutes , so Don't forget to eat the same.
Water Bottles and Cold drinks are sold time to time but they are bit costly. Purchase the same at cheaper cost when train halts any big station like BZA , VSKP , KUR , BBS or CTC.