# Fibonacci Sequence

Learn to generate the Fibonacci sequence.

## We'll cover the following

## Challenge

Write a program to find the index of the first term in the Fibonacci sequence to contain 10 digits?

For this problem, you will have to write two functions:

**1.** `countdigits ( )`

This function takes an integer and returns the number of digits in that integer.

**2.** `printNumberandIndex ( )`

This function creates a Fibonacci sequence and checks whether the latest number generated in the sequence has 10 digits using the **countdigits()** method.

## Example

The Fibonacci sequence is defined by the recurrence relation:

F( n )= F ( n − 1 ) + F ( n − 2 ), where F( 1 ) = 1 and F( 2 ) = 1.

Hence the first 12 terms will be:

F( 1 ) = 1

F( 2 ) = 1

F( 3 ) = 2

F( 4 ) = 3

F( 5 ) = 5

F( 6 ) = 8

F( 7 ) = 13

F( 8 ) = 21

F( 9 ) = 34

F( 10 ) = 55

F( 11 ) = 89

F( 12 ) = 144

The 12th term, F( 12 ), is the first term to contain three digits.

## Coding exercise

Try to solve this challenge on your own. If you can’t solve it, you can look at the solution and explanation below.

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