The main contents of this chapter include all of the following: Basic program structure, C++ syntax, creating a banner, sonnecting strings, character escape sequences, debugging, run-time errors, logic errors.
Trang 1Chapter 2 – Getting Started
Trang 2#include <iostream>
using namespace std;
int main( )
{
cout << “This is C++!”;
}
Header
Primary function Marks beginning of function body
C++ statement Marks end of function body
Location of header files
Lesson 2.1
object
insertion operator used to print to screen
string – characters within double quotes
semicolon: statement terminator
Trang 3Rules for writing statements
Semicolon serve as statement terminator Case sensitivity
Blank spaces
Spacing
Accepted modifications
Lesson 2.1
Trang 4Notes in program describing what code does Perform no action in program
Single line comment structure
– Begin with two slashes (no space between) //
– Line by itself or following statement
Multiline comment structure
– Uses delimiters /* comments */
Lesson 2.2
starts comment ends comment
Trang 5Set of comments at beginning of program
– name
– parameters used
– history
– author
– purpose
– date of program
Lesson 2.2
//*********************** // Name: Sally Student
// Purpose: Assignment 2 // Date: 11/22/2003
// Reference: Chapter 2, #3 //***********************
#include <iostream>
.
Trang 6Programmer must specify new line
Line feeding
– \n in string constant
Lesson 2.3
– endl manipulator
cout << endl<< endl <<“two lines.”;
we can jump
two lines.
Trang 7Can use backslash at end of line to indicate string constant to continue with next line
Lesson 2.3
cout << “This will \ continue on same line.” ; cout << “This will continue on same line.”;
is equivalent to
Trang 8Other escape sequences exist for formatting Full listing in Table 2.1
Examples:
\t horizontal tab
\v vertical tab
\% displays percent character
\” displays double quote
Lesson 2.3
Trang 9Error in program called bug
Process of looking for and correcting bugs Three types of errors
– Syntax
– Runtime
– Logic
Lesson 2.4
Trang 10Mistakes by violating “grammar” rules
Diagnosed by C++ compiler
Must fix before compiler will translate code
Lesson 2.4
coot << endl;
int main ( ( mismatched
parentheses )
Trang 11Violation of rules during execution of program
Computer displays message during
execution and execution is terminated Error message may help locating error
Lesson 2.4
Trang 12Computer does not recognize
Difficult to find
Execution is complete but output is
incorrect
Programmer checks for reasonable and correct output
Lesson 2.4
Trang 13#<include iostream>
using namespace std;
int main ( );
(
cout << ‘Hello world!’
cout << “Hello again”, endl;
// Next line will output
a name!
ccut << “Sally Student”;
/* Next line will
output another name /*
cout << John Senior;
}
# include <iostream>
OK using namespace std;
int main ( ) {
cout << “Hello world!”;
cout << “Hello again”<< endl; // Next line will output a name! cout << “Sally Student”;
/* Next line will output another name */ cout << “John Senior” ;
}
Trang 14General program structure
Rules of C++ syntax
Creating comments and program banners
Using escape sequences to format output
Debugging programs
Three types of errors: syntax, runtime, logic
Chapter 2
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