what does the signed/unsigned comparison warning mean?

Question

auto.cpp: In function ‘int autooo(unsigned int)’:
auto.cpp:33:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]

Answer 1

Type cast the code before you were comparing the signed and unsigned code to avoid warning

int a;
unsigned int b;

if(a==b) gives warning

if(a == (int)b)

will resolve your issue

EDIT

Blind casting will lead to some unexpected results

The warning is because ranges for signed and unsigned are different.

Casting will work fine when signed integer you were used for comparison was greater than zero.

so have check whether the signed integer is greater that zero before comparing

More info here