none
shows up twice in this code snippet:
int none[5]; // declared, not set to anything
And then:
none[i] = number1; // a value has been set, but it's not being used for anything
If, for example, you later had:
int foo = none[3]; // <-- the value in none[3] is being used to set foo
or
for(int i = 0; i < 5; i++) printf("%d\n", none[i]); // <-- the values in none are being used by printf
or something to that effect, we would say none
is “used”, but as the code is, you have: "none" set but not used
; exactly what the compiler said.
In the pastebin link I see your problem:
You wrote this:
for(i=0;i<5;i++) { printf("Question [i]: none[i]+ntwo[i]");
You meant to write this:
for(i=0;i<5;i++) { printf("Question [i]: ", none[i]+ntwo[i]);
Now none
is being used and your print is doing something useful…