How to fill in the random number of China bank credit card?

There are two kinds of credit card verification codes in China Bank: SMS verification code and picture verification code.

Just enter the number of SMS verification codes received by the mobile phone.

There are many forms of picture verification code, which need to be entered according to rules, such as "1+4=?" , you need to fill in the result 5.

Extended data:

Prevent malicious password cracking, ticket brushing, forum flooding and page brushing.

The verification code usually consists of some lines and some irregular characters, and its main function is to prevent some hackers from stealing password data.

References:? Baidu baike