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Perform an action if a condition is true (IF .. THEN)

Given a variable name, if the value is "Bob", display the string "Hello, Bob!". Perform no action if the name is not equal.
cpp
if (name == "Bob") Console::WriteLine("Hello, {0}!", name);
if (name == "Bob") std::cout << "Hello, " << name << "!" << std::endl;

Perform different actions depending on a boolean condition (IF .. THEN .. ELSE)

Given a variable age, if the value is greater than 42 display "You are old", otherwise display "You are young"
cpp
if (age > 42) Console::WriteLine("You are old");
else Console::WriteLine("You are young");
Console::WriteLine("You are {0}", (age > 42 ? "old" : "young"));
std::printf("You are %s\n", (age > 42 ? "old" : "young"));

Perform different actions depending on several boolean conditions (IF .. THEN .. ELSIF .. ELSE)

cpp
if (age > 84) Console::WriteLine("You are really ancient");
else if (age > 30) Console::WriteLine("You are middle-aged");
else Console::WriteLine("You are young");
Console::WriteLine("You are {0}", (age > 84 ? "really ancient" : age > 30 ? "middle-aged" : "young"));
std::cout << "You are " << (age > 84 ? "really ancient" : age > 30 ? "middle-aged" : "young") << std::endl;

Replacing a conditional with many branches with a switch/case statement

Many languages support more compact forms of branching than just if ... then ... else such as switch or case or match. Use such a form to add an appropriate placing suffix to the numbers 1..40, e.g. 1st, 2nd, 3rd, 4th, ..., 11th, 12th, ... 39th, 40th
cpp
#include<iostream.h>
#include<conio.h>
void main()
{
clrscr();
int num,i,x;
cout<<"Enter the range:";
cin>>num;
for(i=1;i<=num;i++)
{
x=i%10;
switch(i)
{
case 11:
case 12:
case 13:cout<<i<<"th ";
continue;
}
switch(x)
{
case 1: cout<<i<<"st ";break;
case 2: cout<<i<<"nd ";break;
case 3: cout<<i<<"rd ";break;
default: cout<<i<<"th ";
}
}
getch();
}

Perform an action multiple times based on a boolean condition, checked before the first action (WHILE .. DO)

Starting with a variable x=1, Print the sequence "1,2,4,8,16,32,64,128," by doubling x and checking that x is less than 150.
cpp
int x = 1;

while (x < 150) { x *= 2; Console::Write("{0},", x); }
Console::WriteLine();
for (int x = 1; x < 150; x *= 2) { std::cout << x << ","; }
std::cout << std::endl;

Perform an action multiple times based on a boolean condition, checked after the first action (DO .. WHILE)

Simulate rolling a die until you get a six. Produce random numbers, printing them until a six is rolled. An example output might be "4,2,1,2,6"
cpp
Random^ rnd = gcnew Random;

int dice = rnd->Next(1, 7); Console::Write("{0}", dice);
do { Console::Write(",{0}", (dice = rnd->Next(1, 7))); } while (dice != 6);
Console::WriteLine();

Perform an action a fixed number of times (FOR)

Display the string "Hello" five times like "HelloHelloHelloHelloHello"
cpp
for(int i = 0; i < 5; ++i) Console::Write("Hello");
for(int i = 5; i > 0; --i) Console::Write("Hello");
dotimes(5, hello);
fill_n(ostream_iterator<string>(cout), 5, "Hello");

Perform an action a fixed number of times with a counter

Display the string "10 .. 9 .. 8 .. 7 .. 6 .. 5 .. 4 .. 3 .. 2 .. 1 .. Liftoff!"
cpp
for(int i = 10; i != 0; --i) Console::Write("{0} .. ", i);
Console::WriteLine("Liftoff!");