Question

If I have

char input[50] = "xFFFF";
int a;

How can I store the numerical value of input in a?
the language is C.

Answer 1

One way to do it might be:

if (sscanf(input, "x%x", &a) == 0) {
    /* matching failed */
}

If your input uses a real hex specifier (like “0xFFFF”) you can just use %i:

if (sscanf(input, "%i", &a) == 0) {
    /* matching failed */
}