for every int x: x+1 > x … is this always true?

Question

I\'m just starting to learn C at school, I\'m trying to get a hold of the basic concepts.

Our homework has a question,

for every int x: x+1 > x

Answer 1

Note for 32-bit number range is [-2147483648, 2147483647] that is equals to [-2³¹, 2³¹ -1 ].

So for expression x+1 > x is true for [-2147483648, 2147483646]

But not for 2147483647 because adding to 2147483647 in 32-bit size number causes bit overflow many implementations it makes x + 1 to -2147483648 But really behavior is Undefined in C standard.

So,

• x + 1 > x True for x in [-2147483648, 2147483646] only
• x + 1 > x , for x = 2147483647 is Undefined value may be True or False depends on compiler. If a compiler calculates = -2147483648 value will be False.