b leaks memory

I guess when you don't allocate enough memory then you write over something else.
I guess when that happens the effect is unpredictable, depending what you wrote over.
If you are lucky then the test passes anyway.

maybe you're a Chinese? you can tell me in Chinese```

I think maybe you're right.
But would you tell me why my code can pass the test?
```I don't know why``In addition I try to delete the "sizeof(char)" only "malloc(2)"remaining, it can also pass through the test.
Maybe the (2) means the compiler allocate 2 address in which each can contain a string?
would you please tell me?

Shouldn't that sizeof(char) in last malloc be sizeof(char*)