Increment

Question

I don't understand the ++a

Answer 1

It increments the value of a by 1, instead of writing a = a + 1 or a += 1, likely because it's a common operation.
The two forms are ++a and a++ which do slightly different things. The first one increments the value before an operation, the other one after, e.g.
int a = 5;
int x = a++; (now x is 5 and a is 6)
vs
int a = 5;
int x = ++a (now x and a are 6)
because in case 2 the value of a was increased before the assignment
(btw I just naturally defaulted to Java syntax but the idea should be clear, just think var instead of int or something)

Answer 2

increment is done by two ways pre increment and post increment as explained above by @Dan for more just go through this
++x increments the value of x before using it
x++ first uses the value of x and then increments it
Eg 1:
x=1
b=++x <-- increment x before assigning to b
print b <--- this will return 2
print x <---this will return 2

Eg 2:
x=1
b=x++ <-- first assign x to b then increment x
print b <--- this will return 1
print x <---this will return 2
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