1000-digit Fibonacci number | Project Euler | Problem #25
URL to the problem page: https://projecteuler.net/problem=25 The Fibonacci sequence is defined by the recurrence relation: F ₙ = F ₙ₋₁ + F ₙ₋₂ , where F₁ = 1 and F₂ = 1. Hence the first 12 terms will be: F₁ = 1 F₂ = 1 F₃ = 2 F ₄ = 3 F₅ = 5 F₆ = 8 F₇ = 13 F₈ = 21 F₉ = 34 F₁ ₀ = 55 F₁₁ = 89 F₁₂ = 144 The 12th term, F₁₂, is the first term to contain three digits. What is the index of the first term in the Fibonacci sequence to contain 1000 digits? #include <iostream> using namespace std ; int main () { const int k = 1000 ; int number [ 3 ][k] = { 0 }, carry, i, counter = 2 ; number [ 2 ][k - 1 ] = number [ 1 ][k - 1 ] = 1 ; while ( number [ 0 ][ 0 ] == ...
