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For example:

                 int a = 10, b = 0;
                 b = ++a;                                    // This is prefix increment operator
                 b = a++;                                    // This is postfix increment operator
                 b = --a;                                    // This is prefix decrement operator
                 b = a--;                                    // This is postfix decrement operator
                 The difference between prefix and postfix (++ and – –) operators is that, in case of prefix operators
                 the value of the variable is incremented/decremented first and then the expression is evaluated.
                 In case of postfix operators, the expression is evaluated first and then the value of the variable is
                 incremented/decremented. Consider the preceding example:

                 int a = 10, b = 0;
                 b = ++a;                    // The value is incremented first and then assigned
                 b = a++;                    // The value is assigned first and then incremented
                 b = --a;                    // The value is decremented first and then assigned
                 b = a--;                    // The value is assigned first and then decremented

                 Program 6: To use prefix increment/decrement operators.
                 #include<iostream.h>
                 #include<conio.h>
                 void main()
                 {
                 clrscr();
                 int a = 10, b = 0, c = 0;

                 cout<<”The old value of a is: “ << a << “\n”;
                 b = ++a;                    //Value is incremented first and then assigned
                 cout<<”The value of a is: “ << a << “\n”;
                 cout <<”The value of b is: “ << b << “\n”;
                 c = --a;                    //Value is decremented first and then assigned
                 cout<<”The value of c is: “ << a << “\n”;

                 getch();
                 }
                 Program 7: To use postfix increment/decrement operators.
                 #include<iostream.h>
                 #include<conio.h>

                 void main()
                 {
                 clrscr();
                 int a = 10, b = 0, c = 0;

                 cout <<”The old value of a is: “ << a << “\n”;
                 b = a++;                    //Value is assigned first and then incremented



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