Because the C language is case sensitive: "I" is not the same as "i"
Change this line:
And in future, don't take photos of your screen and post links to them: copy'n'paste the actual text and post that here, enclosed in cpde blocks by using the
widget above the text box:
<pre lang="C++">#include <stdio.h>
Then displays as:
And we can not only read exactly what you have typed, but we can also copy'n'paste it if we need to compile or test it for you ...
A screenshot doesn't let us do that.