Related Articles
Print Fibonacci sequence using 2 variables
• Difficulty Level : Easy
• Last Updated : 31 May, 2018

Print the Fibonacci sequence. The first Fibonacci numbers are:

## C++

 `// Simple CPP Program to print Fibonacci  ` `// sequence ` `#include ` `using` `std::cout; ` `void` `fib(``int` `n) ` `{ ` `    ``int` `a = 0, b = 1, c; ` `    ``if` `(n >= 0) ` `        ``cout << a << ``" "``; ` `    ``if` `(n >= 1) ` `        ``cout << b << ``" "``; ` `    ``for` `(``int` `i = 2; i <= n; i++) { ` `        ``c = a + b; ` `        ``cout << c << ``" "``; ` `        ``a = b; ` `        ``b = c; ` `    ``} ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` `    ``fib(9); ` `    ``return` `0; ` `} `

## Java

 `// Simple Java Program to print ` `// Fibonacci  sequence ` `import` `java.io.*; ` `class` `GFG { ` ` `  `static` `void` `fib(``int` `n) ` `{ ` `    ``int` `a = ``0``, b = ``1``, c; ` `    ``if` `(n >= ``0``) ` `        ``System.out.print( a + ``" "``); ` `    ``if` `(n >= ``1``) ` `        ``System.out.print( b + ``" "``); ` `    ``for` `(``int` `i = ``2``; i <= n; i++)  ` `    ``{ ` `        ``c = a + b; ` `        ``System.out.print( c + ``" "``); ` `        ``a = b; ` `        ``b = c; ` `    ``} ` `} ` ` `  `    ``// Driver code ` `    ``public` `static` `void` `main (String[] args)  ` `    ``{ ` `            ``fib(``9``); ` `    ``} ` `} ` ` `  `// This code is contributed by anuj_67. `

## Python3

 `# Simple Python3 Program to  ` `# print Fibonacci sequence ` ` `  `def` `fib(n): ` `    ``a ``=` `0` `    ``b ``=` `1` `    ``if` `(n >``=` `0``): ` `        ``print``(a, end``=``' '``) ` `    ``if` `(n >``=` `1``): ` `        ``print``(b, end``=``' '``) ` `    ``for` `i ``in` `range``(``2``, n``+``1``): ` `        ``c ``=` `a ``+` `b ` `        ``print``(c, end``=``' '``) ` `        ``a ``=` `b ` `        ``b ``=` `c ` ` `  `# Driver code ` `fib(``9``) ` ` `  `# This code is contributed  ` `# by Prasad Kshirsagar `

## C#

 `// Simple C# Program to print ` `// Fibonacci sequence ` `using` `System; ` `class` `GFG  ` `{ ` `static` `void` `fib(``int` `n) ` `{ ` `    ``int` `a = 0, b = 1, c; ` `    ``if` `(n >= 0) ` `        ``Console.Write( a + ``" "``); ` `    ``if` `(n >= 1) ` `        ``Console.Write( b + ``" "``); ` `    ``for` `(``int` `i = 2; i <= n; i++)  ` `    ``{ ` `        ``c = a + b; ` `        ``Console.Write( c + ``" "``); ` `        ``a = b; ` `        ``b = c; ` `    ``} ` `} ` ` `  `// Driver code ` `public` `static` `void` `Main ()  ` `{ ` `        ``fib(9); ` `} ` `} ` ` `  `// This code is contributed by anuj_67. `

## PHP

 `= 0) ` `        ``echo` `\$a` `, ``" "``; ` `    ``if` `(``\$n` `>= 1) ` `        ``echo` `\$b` `, ``" "``; ` `    ``for` `( ``\$i` `= 2; ``\$i` `<= ``\$n``; ``\$i``++)  ` `    ``{ ` `        ``\$c` `= ``\$a` `+ ``\$b``; ` `        ``echo` `\$c` `, ``" "``; ` `        ``\$a` `= ``\$b``; ` `        ``\$b` `= ``\$c``; ` `    ``} ` `} ` ` `  `// Driver code ` `fib(9); ` ` `  `// This code is contributed by anuj_67. ` `?> `

Output:

```0 1 1 2 3 5 8 13 21 34
```

How to print using 2 variables isntead of 3 variables?

The algorithm with 2 variables is:
1. print a+b.
3. assign b – a to a.

## C++

 `// CPP Program to print Fibonacci sequence ` `// using 2 variables ` `#include ` `using` `std::cout; ` `void` `fib(``int` `n) ` `{ ` `    ``int` `a = 0, b = 1; ` `    ``if` `(n >= 0) ` `        ``cout << a << ``" "``; ` `    ``if` `(n >= 1) ` `        ``cout << b << ``" "``; ` `    ``for` `(``int` `i = 2; i <= n; i++) { ` `        ``cout << a + b << ``" "``; ` `        ``b = a + b; ` `        ``a = b - a; ` `    ``} ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` `    ``fib(9); ` `    ``return` `0; ` `} `

## Java

 `// Java Program to print  ` `// Fibonacci sequence ` `// using 2 variables ` `import` `java.io.*; ` `class` `GFG { ` `     `  `static` `void` `fib(``int` `n) ` `{ ` `    ``int` `a = ``0``, b = ``1``; ` `    ``if` `(n >= ``0``) ` `        ``System.out.print(a + ``" "``); ` `    ``if` `(n >= ``1``) ` `        ``System.out.print(b + ``" "``); ` `    ``for` `(``int` `i = ``2``; i <= n; i++)  ` `    ``{ ` `        ``System.out.print(a + b + ``" "``); ` `        ``b = a + b; ` `        ``a = b - a; ` `    ``} ` `} ` ` `  `    ``// Driver code ` `    ``public` `static` `void` `main (String[] args)  ` `    ``{ ` `        ``fib(``9``); ` `    ``} ` `} ` ` `  `// This code is contributed by anuj_67. `

## Python3

 `# Simple Python3 Program to ` `# print Fibonacci sequence ` `# using 2 variables ` ` `  `def` `fib(n): ` `    ``a ``=` `0` `    ``b ``=` `1` `    ``if` `(n >``=` `0``): ` `        ``print``(a, end``=``' '``) ` `    ``if` `(n >``=` `1``): ` `        ``print``(b, end``=``' '``) ` `    ``for` `i ``in` `range``(``2``, n``+``1``): ` `        ``print``(a ``+` `b, end``=``' '``) ` `        ``b ``=` `a ``+` `b ` `        ``a ``=` `b ``-` `a ` ` `  `# Driver code ` `fib(``9``) ` ` `  `# This code is contributed by ` `# Prasad Kshirsagar `

## C#

 `// C# Program to print Fibonacci ` `// sequence using 2 variables ` `using` `System; ` ` `  `class` `GFG { ` `         `  `    ``static` `void` `fib(``int` `n) ` `    ``{ ` `        ``int` `a = 0, b = 1; ` `         `  `        ``if` `(n >= 0) ` `            ``Console.Write(a + ``" "``); ` `        ``if` `(n >= 1) ` `            ``Console.Write(b + ``" "``); ` `        ``for` `(``int` `i = 2; i <= n; i++)  ` `        ``{ ` `            ``Console.Write(a + b + ``" "``); ` `            ``b = a + b; ` `            ``a = b - a; ` `        ``} ` `    ``} ` ` `  `    ``// Driver code ` `    ``public` `static` `void` `Main ()  ` `    ``{ ` `        ``fib(9); ` `    ``} ` `} ` ` `  `// This code is contributed by anuj_67. `

## PHP

 `= 0) ` `        ``echo` `\$a` `, ``" "``; ` `    ``if` `(``\$n` `>= 1) ` `        ``echo` `\$b` `, ``" "``; ` `    ``for` `(``\$i` `= 2; ``\$i` `<= ``\$n``; ``\$i``++) ` `    ``{ ` `        ``echo` `\$a` `+ ``\$b` `, ``" "``; ` `        ``\$b` `= ``\$a` `+ ``\$b``; ` `        ``\$a` `= ``\$b` `- ``\$a``; ` `    ``} ` `} ` ` `  `    ``// Driver code ` `    ``fib(9); ` `     `  `// This code is contributed by anuj_67 ` `?> `

Output :

```0 1 1 2 3 5 8 13 21 34
```

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.

My Personal Notes arrow_drop_up
Recommended Articles
Page :