Main program shell
| // Comment header |
| #include <iostream> |
| using namespace std; |
| |
| int main() { |
| // variable
declarations |
| |
| // statements |
| |
| return 0 ; |
| } |
|
|
Variables and data types
| char c; |
// character |
| int i; |
// integer |
| float f; |
// floating point |
| int x = 5; |
// integer, set value |
|
|
|
Operators and expressions
| Assignment |
|
| x = 5 |
// assignment |
| i++ |
// increment |
| j-- |
// decrement |
| |
|
| Arithmetic |
|
| value + 32 |
// addition |
| test - 3 |
// subtraction |
| pi * r |
// multiplication |
| 32 / num |
// division |
| |
|
| Logical |
|
| && |
Logical AND |
| || |
Logical OR |
| ! |
Logical NOT |
| |
|
| Relational |
|
| zz == 44 |
Equal to |
| points != 10 |
Not equal to |
| x < y |
Less than |
| test > 6 |
Greater than |
| wt <= et |
Less than or equal to |
| rad >= 10 |
Greater than or equal |
|
|
| Parentheses |
|
| (x+3) * 5 |
Control order of
operations with parens |
|
|
|
|
Decisions (if, else, switch)
| Simple if |
| if( expr) { |
| //
statements |
| } |
| |
| If-then-else |
| if( expr) { |
| //
statements |
| } else if( expr) { |
| //
statements |
| } else { |
| //
statements |
| } |
| |
| Switch |
| switch( expr) { |
| case
constant: |
|
// statements |
|
break; |
| case
constant: |
|
// statements |
|
break ; |
| ... |
| default: |
|
// statements |
| } |
|
|
Looping
| While loop |
| while( expr) { |
| //
statements |
| } |
|
| Do-while loop |
| do { |
| //
statements |
| } while( expr); |
|
| For loop |
| for( initialize-expr;
test-expr; |
|
update-expr) { |
| //
statements |
| } |
|
|
Standard input and output
| Getting input |
| cin
>> value; |
| |
| Writing output |
| cout
<< "Hello world"; |
| cout
<< "Number " << x << endl; |
|
|
|