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

Do i have the correct format character?

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

I keep being told i dont have the correct format character and treehouse reminds me that i should be using %ld but I am?

float real_numbers[5];
printf("real_numbers %ld bytes\n", sizeof(real_numbers));
printf("float %ld bytes\n", sizeof(float));
printf("Array real_numbers %ld bytes\n", sizeof(real_numbers)/ sizeof(float));

2 Answers


You pretty much have to code down except for some minor things. Just needed the "Array" in front of real_numbers and a "." after bytes on the second and fourth line of code. As far as the 3rd line "printf("float %ld bytes\n", sizeof(float));" you wouldn't need that because that is essentially your second line of code 'printf("Array real_numbers is %ld bytes.", sizeof(real_numbers));'

You have to type everything to the "T" or else the code challenges wont pass you, hope that helps.

float real_numbers[5]; Challenge 1 printf("Array real_numbers is %ld bytes.", sizeof(real_numbers)); Challenge 2 printf("Array real_numbers can store %ld items.", sizeof(real_numbers)/sizeof(float)); Challenge 3