获取以逗号分隔的输入 + 获取输入的问题

Question

I'm trying to get the input of a user in the following param1,param2,param3 problem is that I'm not allowed to use scanf. I want to retrieve those 3 parameters into 3 different variables but: - I don't know how to get them because they're separated by a comma - I can't manage to use well sscanf and from what I've seen, I don't think fgets can help me. Ex:

char a1, a2, a3;
printf("Enter data\n");
sscanf(input,"%[^,],%[^,],%[^,]", &a1, &a2, &a3);

I'm not asked to type the arguments that I want. Is there something I'm missing here?

Answer 1

You can use fgets and sscanf like:

char input[10];
char a1, a2, a3;

if (fgets(input, sizeof input, stdin))
{
    if (sscanf(input, "%c,%c,%c", &a1, &a2, &a3) == 3)
    {
        // ok - go on and use a1, a2, a3
    }
    else
    {
        // not good, the input doesn't match the pattern
    }
}
else
{
    // not good, didn't get any input
}

Answer 2

If you are not allowed to use scanf , I doubt using a variation of it like sscanf will be allowed. It seems the point of the exercise is that you learn how to manually parse a string.

To do that, you can take several approaches. One is reading the entire line in memory and then parsing it. Another is going character by character and doing the parsing at the same time as the reading.

Whatever you do, you have to make a loop and scan for the comma , character (to know when to go to the next argument) and the end line \n one (to stop in the last one), while copying the other characters into each string.