How to read and write data in C++ (random access)?

[Man4ish]

Hi,

I have one input data.

1200 3
1234 4
1235 6
1236 2

I need write this in binary file in such a way that i can easily write and read the data.

I know using fread and fwrite it is possible to do it. we can access data randomly. But how can i implement it? Any working example will help me.

[weaknessforcats]

Use a struct:

struct
{
  int data;
  int data1;
};

Load the members and then write the struct in binary to your file. You on't need the separating space on the output.

Read the input using fscanf into an int, a char, and an int. Use the ints to load yout struct.

[Man4ish]

But i want to write data in such a way that 3 should be stored at 1200 loction and like others and i can easily read the data from there also.

Regards

[weaknessforcats]

In that case use a text file instead of a binary file and be sure to write each record in the file in exactly the same format.

A struct and a binary file will still work since the file would contain nothing but ints that are all the same size. The int with 1200 would be followed by an int with 3 followed by an int with 1234.

Remember, after the file is written there is no way to tell howit was written just from the data in the file. It is up to you to position the data so you can access it randomly later. In this case, do you see the data as 4 characters 1234 or an integer of 1234. The answer to that will determine how to format the file.