问题
I want to store a letter into a variable so that whenever the program starts again it can use the variable in further program execution.
What is the way to achieve this?
回答1:
No, you cannot achieve this using variables. variables only exist untill the program finishes execution. Once the program is finished, no variable is retained.
You need to make use of file i/o. You can write the end (final) data of one execution to a file, the next time program runs, it can read the file contains and resume the exection.
For your reference,
In C
you can check below library functions
- fopen()
- fclose()
- fread()
- fwrite()
- fprintf()
- fgets()
and their families.
In C++
- <fstream>
来源：https://stackoverflow.com/questions/30345307/i-want-to-store-a-value-even-after-my-program-ends