STANDARD OPERATIONS AND FUNCTIONS
Arithmetic Operations
Operation Order
Increment and Decrement Operators
Assignment Operators
Boolean Operations
Logical Operators
Standard Functions
String Functions
Arithmetic Operations
add +
subtract -
multiply *
divide /
remainder %
force = mass * accel;
average = total / SIZE;
r = x + y*z - q/h;
11 / 3 is 3
11.0 / 3 is 3.6667
11 % 3 is 2
Can perform arithmetic operations on character data
Operation Order
Within parentheses
*, /, % left-to-right
+, - left-to-right
Good rule of thumb: Use Parentheses!
s = t / (a + s * (x-z)) + q;
Increment and Decrement Operators
increment ++
decrement --
int, float, char
++count; // count = count + 1;
--drop; // drop = drop - 1;
++x ... pre-increment
x++ ... post-increment
Suppose x=7, y=5...
a = ++x; // x=8, a=8
b = y++; // y=6, b=5
Pre/post-decrement work same way
``C++ = language one better than C''
Assignment Operators
= simple assignment
+= addition assignment
slug += zig*zag; // slug = slug + zig*zag;
-= subtraction assignment
drop -= few; // drop = drop - few;
*= multiplication assignment
/= division assignment
Boolean Operators
Boolean Operators result in
false
true
== equal to
(sum == SIZE)
result is 1 if sum equal SIZE
result is 0 if sum not equal SIZE
does not change sum or SIZE
Be very careful!
(sum = SIZE)
changes sum to SIZE
result is SIZE (false if 0, true otherwise)
!= not equal to
(sum != SIZE)
< less than
(sum < SIZE)
<= less than or equal to
> greater than
>= greater than or equal to
Logical Operators
! not
!(sum > SIZE)
|| or
(sum = SIZE) || (flag > stopper)
&& and
Standard Functions
#include
#include
#include
abs(x) -- absolute value of x
cos(x) -- cosine of x
pow(x,y) -- x to the y power
rand() -- random number
sqrt(x) -- square root of x
String Functions
#include
char bob[20];
char job[10]="Sales";
char mob[10]="person";
char rob[20];
bob = job; // doesn't really work
just copies address
if change job, changes bob as well
strcpy(bob,job); // bob is now "Sales"
strcat(bob,mob); // bob is now "Salesperson"
strcmp(bob,rob) -- is bob same as rob?