Created: 2022-08-19
Tags: #fleeting
Two syntax for incrementation and decrement
++xx++,n++ increments n AFTER its value has been used.
If n = 5,
then n++; nothing changes, therefore n is still 5
But, if I somehow used the variable n somewhere
like n + 0, the increment now happens and turns 5 to 6
++n, immediately increments n
If n = 5;
then x = ++n; immediately sets x to 6
Because it affects the logic of a program
Practical example of taking advantage of this little detail
// Code #1
int j = 0;
while (True)
s[j++] = a;
^ Compiler sees j++, the value of j remains at 0
^ The next loop, the j++ is called again, this is where j increments thus j's value now is 1
Still don't get it?
Code below shows obvious differences between n++ and ++n
n++ Exampleint n = 0;
while (n < 5)
printf("%i", n++);
^ This will output 0, 1, 2, 3, 4
Here, incrementation only happens when n is used again.
That's why it was able to print 0 because incrementation didn't happen yet.
++n Exampleint n = 0;
while (n < 5) // It shouldn't print 5 but...
printf("%i ", ++n);
^ This will output 1, 2, 3, 4, 5
The reason it was able to print 5 even tho condition n < 5 doesn't permit it
Because in reality, it's actually 4 < 5, incrementation didn't happen yet
When it got printed, the ++ incremented 4 thus making it print 5