Yes, you can buy and sell a stock designated under the CNC (Cash and Carry) delivery code on the same day, provided your broker permits intraday trade squaring or you have adequate holdings. However, if you purchase shares using CNC with the intention of holding them for delivery, executing a sale on the exact same trading session is typically treated as an intraday square-off or short-term trade depending on the specific exchange rules and broker software mechanisms. It is essential to check your specific trading platform's policies regarding delivery versus intraday product codes to avoid unintended brokerage penalties or settlement mismatches.