increment operator
DESCRIPTION
Increment Operator. To increment a variable X by 1. X+1;X+=;++X; X = 10 Y = X + 1;Y = 11 X += 1;X = 11 Y = ++X + 4;Y = 15. Increment Operator. To increment a variable X by 1. X+1;X+=;++X; Operator before the variable are called prefix . X = 10 - PowerPoint PPT PresentationTRANSCRIPT
Increment Operator
• To increment a variable X by 1.
X+1; X+=; ++X;
X = 10
Y = X + 1; Y = 11
X += 1; X = 11
Y = ++X + 4; Y = 15
Increment Operator
• To increment a variable X by 1.
X+1; X+=; ++X;
• Operator before the variable are called prefix.
X = 10
X = X + 1; X = 11
X += 1; X = 12
Y = ++X + 4; Y = 17
Example 6
#include<iostream.h>
int main()
{
int x, y;
x=10; //initial value for x
x=x+1; //increment x by 1
cout <<"x=" <<x
<<endl;
x+=1; //increment x by 1
cout <<"x=" <<x
<<endl;
y=++x+4; //increment x by 1 and add 4
cout <<"y=" <<y <<"\t and \t x=" <<x
<<endl;
return 0;
}
Increment Operator
• The operator can also be written after the variable to which it applies.
• Operator before the variable are called postfix.
• Effect of postfix in operation is slightly different. The incrementing of the variable to which it applies occurs after its value is used in context.
Example 7
#include<iostream.h>
int main()
{
int x, y;
x=10; //initial value for x
x=x+1; //increment x by 1
cout <<"x=" <<x
<<endl;
x+=1; //increment x by 1
cout <<"x=" <<x
<<endl;
y=4 + x++ ; //add 4 to x and increment x by 1
cout <<"y=" <<y <<"\t and \t x=" <<x
<<endl;
return 0;
}
Decrement Operator
• To decrement a variable X by 1.
X = X - 1
--X
X--
-=X
Example 8
#include<iostream.h>
int main()
{
int x, y, z;
x=10; //initial value for x
x=x-1; //decrement x by 1
cout <<"x=" <<x
<<endl;
x-=1; //decrement x by 1
cout <<"x=" <<x
<<endl;
y=--x +4; //decrement x by 1 and add 4
cout <<"y=" <<y <<"\t and \t x=" <<x
<<endl;
z=4 + x--; //add 4 to x and decrement x by 1
cout <<"z=" <<z <<"\t and \t x=" <<x
<<endl;
return 0;
}
Relational Operators
• < less than
• <= less than equal
• > greater than
• >= greater than equal
• == equal to
• != not_eq not equal to
Logical Operators
• ! not logical NOT
• && and logical AND
• || or logical OR
Bitwise Operators
• Bitwise operators treat their operands as a series of individual bits rather than a numerical value.
• They work with integer or constants.
Bitwise Operators
• ~ comp1 one’s complement
• << left shift
• >> right shift
• & bitand bitwise And
• ^ xor bitwise Exclusive-OR
• | bitor bitwise OR
Example 9
#include<iostream.h>
main()
{
long letter1 =0x41, letter2 =0x5A, x=0, y=0, z=0;
cout <<"letter1=" <<letter1 <<"\t\t letter2=" <<letter2;
cout <<endl;
x= ~letter1;
y=letter1 & letter2;
z=letter1 | letter2;
cout <<"x= " <<x <<"\t\t y=" <<y <<"\t\t z=" <<z;
cout <<endl;
return 0;
}
Assignment Operators
• = assignment
• += addition update
• -= subtraction update
• *= multiplication update
• /= division update
Assignment Operators
• %= modulus update
• <<= left shift update
• >>= right shift update
• &= and_eq bitwise AND update
• |= or_eq bitwise OR update
• ^= xor_eq bitwise Exclusive-OR
If Statement
• The if statement enables the programmer to test for a condition and branch to different parts of the code depending on the result.
If (expression)
statement;
Example 10
#include<iostream.h>
main()
{
int w, x, y, z;
cout <<"enter a value for w" << endl <<"w=";
cin>>w;
cout <<"enter a value for x" << endl <<"x=";
cin>>x;
if (w>x)
{
y=w+x;
cout <<"w is greater than x" <<endl <<"y=w+x=" <<y <<endl;
}
if (w<x)
{
z=w-x;
cout <<"x is greater than w" <<endl <<"z=w-x=" <<z <<endl;
}
if (w==x)
cout <<"A tie" <<endl;
cout <<"Thanks for telling me. \n\n";
return 0;
}
The else keyword
• A program should take one branch if a condition is true, and another branch if the condition is false.
if (expression)
statement;
else
statement;
Example 11
#include<iostream.h>
main()
{
int w, x, y, z;
cout <<"enter a value for w" << endl <<"w=";
cin>>w;
cout <<"enter a value for x" << endl <<"x=";
cin>>x;
if (w>x)
{
y=w+x;
cout <<"w is greater than x" <<endl <<"y=w+x=" <<y <<endl;
}
else
{
z=w-x;
cout <<"x is greater than w" <<endl <<"z=w-x=" <<z <<endl;
}
cout <<"Thanks for telling me. \n\n";
return 0;
}
Advanced if statement
• Any statement can be used in an if or else clause. if (expression1)
{
if (expression2)
statement1;
else
{
if (expression3)
statement2;
else
statement3;
}
}
else
statement4;
Switch Statement
• The switch statement enables you to select from multiple choice on a set of fixed values for a given expression.
Example 12#include<iostream.h>
main()
{
int x=0;
cout <<"Please select one of the following delicious dishes:" << endl
<<"1 \t Hamburger" <<endl
<<"2 \t Hamburger and coke" <<endl
<<"3 \t Coke" <<endl;
cout <<"Enter your choice \t";
cin>>x;
switch(x)
{
case 1: cout << endl <<"Hamburger" <<endl;
break;
case 2: cout << endl << "Hamburger and coke" <<endl;
break;
case 3: cout << endl << "Coke" <<endl;
break;
default: cout <<"You entered a wrong number" <<endl;
}
return 0;
}
Loop
• A loop executes a sequence of statements until a particular condition is true (or false).
loop:
statements
if ( )
goto loop;
Example 13
#include<iostream.h>
int main()
{
int i=1,y=20, x;
loop:
x=y+i;
cout <<"x=" <<x <<"\t i=" <<i <<"\t y=" <<y <<endl;
if (++i <= y)
goto loop;
cout <<"I love C++" <<endl;
return 0;
}
for Loop
• General form of the for loop is:
for (initializing; test; increment)
statements;
Example 14
#include<iostream.h>
int main()
{
int i=1,y=20, x;
for(i;i<=y;i++)
{
x=y+i;
cout <<"x=" <<x <<"\t i=" <<i <<"\t y=" <<y <<endl;
}
cout <<"I love C++" <<endl;
return 0;
}
Example 15
#include<iostream.h>
int main()
{
int y=20, x;
for(int i=1;i<=y;i++)
{
x=y+i;
cout <<"x=" <<x <<"\t i=" <<i <<"\t y=" <<y <<endl;
}
cout <<"I love C++" <<endl;
return 0;
}
Example 16
#include<iostream.h>
int main()
{
int i=1, y=20, x;
for(; i<=y; i++)
{
x=y+i;
cout <<"x=" <<x <<"\t i=" <<i <<"\t y=" <<y <<endl;
}
cout <<"I love C++" <<endl;
return 0;
}
Example 17
#include<iostream.h>
int main()
{
int i=1, y=20, x;
for(;i<=y;x=y+i++, cout <<"x=" <<x <<"\t i=" <<i <<"\t y=" <<y <<endl);
cout <<"I love C++" <<endl;
return 0;
}