There could be some code that will never be executed because of their conditional evaluation which will always return false; such dead code can be effictively removed to save gas.
function nameFunction(uint256 number) public pure {
if(number < 0) {
if(number > 2) {
// this part of the code will never be execued
return number;
}
}
}
Avoid using dead code in the contract to save gas.