One thing Embedded engineer should know is integer promotion rule. Declaring the variable in correct makes life lot more easy in debugging and it should a good practice of programming as well.
Below example is for integer promotion rule.
unsigned int uIntVar = 2;
int intVar = -10;
(uIntVar+intVar > 2) ? puts("> 2") : puts("<= 2");
Answer is >2. Expression having the signed and unsigned integers, signed integer becomes a large number and evaluates to positive number in above example.
However it becomes a negative number if
int result = intVar + uIntVar; Or type cast the result to int
Now let me post questions.
1) What is the return value if invoke malloc with size zero?
2) How do you write a 1's compliment for given number?
Answer for the first question is strange where second one tests whether you are a embedded engineer.
Below example is for integer promotion rule.
unsigned int uIntVar = 2;
int intVar = -10;
(uIntVar+intVar > 2) ? puts("> 2") : puts("<= 2");
Answer is >2. Expression having the signed and unsigned integers, signed integer becomes a large number and evaluates to positive number in above example.
However it becomes a negative number if
int result = intVar + uIntVar; Or type cast the result to int
Now let me post questions.
1) What is the return value if invoke malloc with size zero?
2) How do you write a 1's compliment for given number?
Answer for the first question is strange where second one tests whether you are a embedded engineer.
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