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iOS Objective-C Basics (Retired) Pointers and Memory Array Size and Length

Shaun Kelly
Shaun Kelly
5,648 Points
Posted by Shaun Kelly
Shaun Kelly
5,648 Points

Having trouble with finding the length of this array for a code challenge.

It's saying that I have the format character wrong?

float real_numbers[5];
printf("Array real_numbers is %ld bytes", sizeof(real_numbers));
printf("Array real_numbers can store %ld items", sizeof(real_numbers));

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

to find the length of an array (the number of items it stores, not the size in bytes) you need to divide the size of the array by the size of the data type of the array. In this case your array stores floats, so divide the sizeof the array by the size of the float data type:

float real_numbers[5];
printf("Array real_numbers is %ld bytes", sizeof(real_numbers));
printf("Array real_numbers can store %ld items", sizeof(real_numbers)/sizeof(float));