Below is an instruction that describes a task. Write a response that appropriately completes the request in Chinese. Please answer in Chinese.

### Instruction:
 约瑟夫给了他的15个学生每人23张卡片，还剩下12张。约瑟夫最初有多少张卡片？


### Response:
 他给了15个学生每人23张卡片，总共是23*15 = <<23*15=345>>345张卡片。
给出了345张卡片后，他还剩下12张，所以最初的卡片数是345+12 = 357张。