Additional Operator_Format - AdditionalOperators and...

Additional Operators
and
Math functions in C++

Increment & Decrement
Operators
•
Increment operator: increase variable by 1
•
Decrement operator: decrease variable by 1
•
Pre-increment: ++variable
•
Post-increment: variable++
•
Pre-decrement: --variable
•
Post-decrement: variable--

Increment & Decrement Operators
•
++count; or count++; increases the value of count by 1
•
--count; or count--; decreases the value of count by
1
•
If x = 5; and y = ++x;
x y
it is the same as 2 statements
x = x + 1;
y = x ;
–
After the second statement both
x
and
y
are
6
•
If x = 5; and y = x++;
it is the same as 2 statements
y = x ;
x = x + 1;
–
After the second statement
y
is
5
and
x
is
6
? 5
6 6
5
5 6
?

Assignment Statements
•
C++ has special assignment statements called
compound assignment: += , -= , *= , /= , and %=
•
Example: x y a
–
int x = 2, = 3, a = 4 ; 2 3 4
–
x *= y;  x = x * y ; 6 3 4
–
x += y + 2 ;  x = x + (y + 2) ;11 3 4
–
x -= y;  x = x – y ; 8 3 4
–
x /= y + a - 3 ;  x = x/(y+ a - 3);2 3 4
–
x %= y ;  x = x % y ; 2 3 4
–
x %= y -1 ;  x = x % (y-1); 0 3 4
–
y /= x + 2;  y = y / (x + 2) ; 0 1 4
–
a /= ++x + y++;  a=a/(++x + y++); 1 2 2
++x;
a = a /(x+y) ;
y++;

System Mathematical Functions
Purpose Function Name Prototype/Signature Usage Notes
Computes cosine cos double cos (double X); X must be in radians!
Computes sine sin double sin (double X);
Computes tangent tan double tan (double X);
Computes arc cosine acos double acos (double X); Return value is in radians.