No Such file or folder in directory

Sometimes when i do coding in CPP N IDE. It doesn't compiles the code. It says g++;no such file in directory.
Why what is wrong with it.
Yesterday I was using loops and the problem appeared again.

[Et7f3]

Try to remove space in name

Try to remove space in name

Okay

[Et7f3]

It worked ?

It worked ?

Yes, Thank you

[Hadi-Jdeed]

Why?