Increment Operator

1. 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

2. 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

3. 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; }

4. 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.

5. 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; }

6. Decrement Operator • To decrement a variable X by 1. X = X - 1 --X X-- -=X

7. 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; }

8. Relational Operators • < less than • <= less than equal • > greater than • >= greater than equal • == equal to • != not_eq not equal to

9. Logical Operators • ! not logical NOT • && and logical AND • || or logical OR

10. Bitwise Operators • Bitwise operators treat their operands as a series of individual bits rather than a numerical value. • They work with integer or constants.

11. Bitwise Operators • ~ comp1 one’s complement • << left shift • >> right shift • & bitand bitwise And • ^ xor bitwise Exclusive-OR • | bitor bitwise OR

12. 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; }

13. Assignment Operators • = assignment • += addition update • -= subtraction update • *= multiplication update • /= division update

14. 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

15. 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;

16. 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; }

17. 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;

18. 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; }

19. 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;

20. Switch Statement • The switch statement enables you to select from multiple choice on a set of fixed values for a given expression.

21. 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; }

22. Loop • A loop executes a sequence of statements until a particular condition is true (or false). loop: statements if ( ) goto loop;

23. 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; }

24. for Loop • General form of the for loop is: for (initializing; test; increment) statements;

25. 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; }

26. 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; }

27. 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; }

28. 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; }