Accelerated C + + Learning notes and----Chapter II

This section mainly explains:

While statement

If statement

For statement

logical operators.

The new types that are designed in this section are:

BOOL Boolean value

Unsigned non-negative integers

Short at least 16-bit integer

Long

size_t unsigned integer type, which can hold the length of any object

String::size_type unsigned integer type, which can store the length of any string

Source code in the book: Frame.cpp

#include <iostream> #include <string>//say what standard-library names we useusing namespace Std;int main () {/  /ask for the person's namecout << "Please enter your first name:"//Read the namestring name;cin >> name;// Build the message, we intend to writeconst string greeting = "Hello," + name + "!"; /The number of blanks surrounding the greetingconst int pad = 1;//The number of rows and columns to writeconst int rows = Pad * 2 + 3;const string::size_type cols = greeting.size () + pad * 2 + 2;//write a blank line to separate the output FR Om the inputcout << endl;//write ' rows ' rows of output//Invariant:we has written ' r ' rows so farfor (int r = 0; R! = rows; ++r) {String::size_type c = 0;//Invariant:we has written ' C ' characters so far in the current rowwhile (c! = cols) {//  Is it time to write the greeting?if (r = = pad + 1 && c = = pad + 1) {cout << greeting;c + + greeting.size ();} else {//is we on the border?if (r = = 0 | | r= = Rows-1 | | c = = 0 | | c = = cols-1) cout << "*"; Elsecout << ""; ++c;}} cout << Endl;} return 0;}

Exercises

2-1

Change the code pad above to 0

2-2

#include <iostream> #include <string>//say what standard-library names we useusing std::cin; Using std::endl;using std::cout; Using Std::string;int Main () {//ask for the person ' s namecout << "Please enter your first name:"//Read the Namest Ring Name;cin >> name;//Build the message that we intend to writeconst string greeting = "Hello," + name + "!"; /The number of blanks surrounding the greetingconst int h_pad = 1;const int v_pad = 2;//the number of rows and columns T  o writeconst int rows = V_pad * 2 + 3;const string::size_type cols = greeting.size () + H_pad * 2 + 2;//write a blank line To separate the output from the Inputcout << endl;//write ' rows ' rows of output//Invariant:we has written ' R ' r OWS so farfor (int r = 0; R! = rows; ++r) {String::size_type c = 0;//Invariant:we has written ' C ' characters so far in T He current rowwhile (c! = cols) {//Is it time to write the greeting?if (r = = V_pad + 1 && c = = H_pad + 1) {cout &lt ;< GreeTing;c + = Greeting.size ();} else {//is we on the border?if (r = = 0 | | r = = ROWS-1 | | c = = 0 | | c = = cols-1) cout << "*"; Elsecout << ""; ++c;}} cout << Endl;} return 0;}

2-3

#include <iostream> #include <string>//say what standard-library names we useusing namespace Std;int main () {/  /ask for the person's namecout << "Please enter your first name:"//Read the namestring name;cin >> name;// Build the message, we intend to writeconst string greeting = "Hello," + name + "!";    /The number of blanks surrounding the greetingint pad;    cout << "Please input the number of the space:"; CIN >> pad;//The number of rows and columns to writeconst int rows = Pad * 2 + 3;const string::size_type cols = GRE Eting.size () + pad * 2 + 2;//write a blank line to separate the output from the Inputcout << endl;//write ' rows ' r oWS of output//Invariant:we has written ' r ' rows so farfor (int r = 0; R! = rows; ++r) {String::size_type c = 0;//Inva Riant:we has written ' C ' characters so far in the current rowwhile (c! = cols) {//Is it time to write the greeting?if ( r = = Pad + 1 && c = = pad + 1) {cout << GreetiNg;c + = Greeting.size ();}    else {//is we on the border?if (r = = 0 | | r = = ROWS-1 | | c = = 0 | | c = = cols-1) cout << "*"; Elsecout << ""; ++c;}} cout << Endl;} return 0;}

2-4

#include <iostream> #include <string>//say what standard-library names we useusing std::cin; Using std::endl;using std::cout; Using Std::string;int Main () {//ask for the person ' s namecout << "Please enter your first name:"//Read the names Tring name;cin >> name;//Build the message that we intend to writeconst string greeting = "Hello," + name + "!"; /The number of blanks surrounding the greetingconst int pad = 1;//The number of rows and columns to writeconst int rows = Pad * 2 + 3;const string::size_type cols = greeting.size () + pad * 2 + 2;const string spaces = String (Greeting.size () + Pad * 2, ');//write a blank line to separate the output from the Inputcout << endl;//write ' rows ' rows of output  Invariant:we has written ' r ' rows so farfor (int r = 0; R! = rows; ++r) {String::size_type c = 0;//Invariant:we has Written ' C ' characters so over the current rowwhile (c! = cols) {//Is it time to write the greeting?if (r = = Pad + 1 & amp;& c = = Pad + 1) {cout << greeting;c + = Greeting.size ();} else {//is we on the border?if (r = = 0 | | r = = ROWS-1 | | c = = 0 | | c = = cols-1) {cout << "*"; ++c;} else if (r = = Pad + 1) {cout << ""; ++c;} else {cout << spaces;c + = Spaces.size ();}}} cout << Endl;} return 0;}

2-5

#include <iostream>using namespace Std;int main () {    int length;    cout << "This program was intend to print a square and triangle:" << Endl;    cout << "Please input the length of border:";    cin >> length;    Print the square for    (int i = 0; i<length; i++)    {for        (int j = 0; J < length; J + +)        {            if (I ==0 | | i = = length-1)            {                cout << "*";            }            Else                if (j = = 0 | | j = = length-1)                    cout << "*";                else cout << "";        }        cout << Endl;    }    Print triangle .....    such as ..... ....    . return 0;}

............ The rest of the ellipsis is the contact loop and control flow ....

Accelerated C + + Learning notes and----Chapter II