split a string and get the last part using C

Question

I have a string "some random data/1000". Now, I want the number(1000) alone without storing the first part anywhere. I should directly get the last part i.e the number. How to do this in C language?

Here '/' is delimiter.

There we are storing every part. Here I do not need to store the first part. My work is only with the numerical data at the end. Infact, the strings are large to store the first part. — mit23, Feb 19 '15 at 13:21

score 2 · Answer 1 · answered Feb 19 '15 at 13:21

If you're certain there's only one delimiter, I would simply use strrchr()¹ to find it. Then either directly convert the number to integer (using e.g. strtol()) or allocate a new string and copy the trailing part of the first in there.

¹ Please note that middle r, it's searching backwards.

score 0 · Accepted Answer · edited May 23 '17 at 12:29

0

There are many ways to do it, but in your particular case

char  string[]      = "some random data/1000";
char *pointerTo1000 = strchr(string, '/');
if (pointerTo1000 != NULL)
{
    pointerTo1000 += 1;
    printf("%s\n", pointerTo1000);
}

should output 1000, if you want to covert it to a number

char *endptr;
int value = strtol(pointerTo1000, &endptr, 10);
if (*endptr == '\0')
    printf("converted successfuly: %d\n", value);

if some random data contains a slash / then strrchr suggested by unwind is the right choice, and you can use it exactly as in my example.

edited May 23 '17 at 12:29

Community

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answered Feb 19 '15 at 13:21

Iharob Al Asimi

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avoid `printf("%s\n", pointerTo1000);` with `pointerTo1000` being NULL. There are systems (e.g. solaris) where that crashes – Ingo Leonhardt Feb 19 '15 at 13:33

split a string and get the last part using C

2 Answers2