I know that in C I can get the length of a char array by using strlen() but how do I get the length of an integer array. Is there a function in a library somewhere?
1 Answer
In general, you cannot obtain the length of an array unless the array includes a pre-determined terminating sentinel. So, a C string is the canonical example of an array that has a pre-determined terminating sentinel, namely the null terminator.
You will need to keep track of the length of the array in a separate variable, or use a terminating sentinel.
An example of the latter would be an array declared like this:
int array[] = { 1, 2, 42, -1 };
where -1 is deemed to be the terminator. That technique is only viable when you can reserve a value for use as a terminator.
I'm assuming that you are looking to obtain the length of a dynamically allocated array, since that is the most likely scenario for the question to be asked. After all, if your array is declared like this, int array[10], then it's pretty obvious how long it is.
answered Jul 29, 2013 at 9:58
David Heffernan
616k46 gold badges1.1k silver badges1.5k bronze badges
-1at the end).strlenuses terminating null character to find the length, you need something similar for int array, otherwise not possiblestrlenis not for testingchararrays but for testing C strings, that arechararrays plus a special convention for termination.