Include Headers
#include |
<headerfile> |
Common Headers / Libraries |
#include <stdio.h> |
I / O functions |
#include <string.h> |
string functions |
#include <time.h> |
time functions |
#include <stdlib.h> |
memory, rand, ... |
#include <math.h> |
math functions |
#include <iostream.h> |
#include <fstream.h> |
I / O file functions |
#include "myfile.h" |
Insert file in current directory |
Comments
// One line comment text |
/* multiple line block comment text */ |
Basic Variable Types
|
NUMBER int a; float a;
|
|
CHARACTER char car; string s;
char car = ‘c’; string s = “hola mon”;
|
|
BOOL bool b = false/true;
|
Basic input / Output Operators
cin |
cin >> var |
cout |
cout<<"The variable has"<<var |
Basic Operators / Math Operators
+ Add |
- Less |
* Mult |
/ Div |
% Mod |
++var / --var |
var++ / var-- |
|
|
Conditionals
A == B |
if A is equal to B, this is true; otherwise, it’s false |
A != B |
if A is NOT equal to B, this is true; otherwise, it’s false |
A < B |
if A is less than B, this is true; otherwise, it’s false |
A > B |
if A is greater B, this is true; otherwise, it’s false |
A <= B |
if A is less than or equal to B, this is true; otherwise, it’s false |
A >= B |
if A is greater or equal to B, this is true; otherwise, it’s false |
A ! B |
if A |
A && B |
if condition A and condition B are true, this is true; otherwise, it's false. |
A || B |
if condition A or condition B is true, this is true; otherwise, it's false. |
Boolean expressions in C++ are evaluated left to right!
Arrays
|
type array_name [ # of elements ]; int price [10];
|
|
type array_name [# elements] [# elements]; int price [5] [10];
|
· Array index starts at 0.
· Ex: Access 3rd element : cout<<price [2];
Control Flow
if sentence |
|
if ( conditional ) {
// do something
}
else if ( another_conditional ) {
// do something else
}
else {
// do something as default
} |
while sentence |
|
while ( conditional ) {
// do something
}
placing “break;” breaks out of the loop.
placing “continue;” jumps to next loop. |
for sentence |
|
for ( init; test; command ) {
// do something
}
"break;" and "continue;" identical effects. |
do while sentence |
|
do {
//do something
} while (bool expression); |
switch case sentence |
|
switch ( variable )
{
case value1:
// do something;
break;
case value2:
// do something else;
break;
[default:
// do something by default:
break; ]
} |
|
|
File Input / Output
#include <fstream.h>
ifstream file; //read buffer
ofstream file; //write buffer
file.open ("filename", [file mode constant]);
//Test if the file was created
if(fs.is_open()) if(fs)
//Reads/Writes like cin and cout
file >> var; //Read
file << ''Text: "<< var << endl; //Write
//Read Entire line
getline (file,String);
//Read until it arrives at the end of file
while(file.eof())
//Detect if the read/write fail
if(file.fail())
//Close File
file.close();
|
File Mode Constants
ios::in //Opens file for reading
ios::out //Opens file for writing
ios::app //Causes output to be appended at EOF
ios::trunc //Destroys the previous contents
ios::nocreate //Causes open() to fail if file doesn't already exist
ios::noreplace //Causes open() to fail if file already exists
Procedures
//Declaration
void ProcedureName()
{
// do something
}
//Call to procedure
ProcedureName();
|
In the procedures we don't receive variables and don't return other variable.
Functions
//Declaration
[returnType] functionName ( [input1Type input1Name, input2Type input2Name, ....] )
{
// do something
return value; // value must be of type returnType
}
//Call to function
[returntype var =] functionName ([input1Type input1Name, input2Type input2Name, ....])
|
We have two methods to create and call functions:
passed with values and passed for reference.
Pass by reference : we put & before variable in the declaration.
Structures
Structure declaration : |
struct <structure_name>
{
<type> <name>, <name>, ... ;
<type> <name>, <name>, ... ;
} |
Var declaration with structure type : |
<structure_name> var_name; |
Acces to structure : |
var_name.name; |
|
Created By
Metadata
Favourited By
Comments
No comments yet. Add yours below!
Add a Comment
Related Cheat Sheets