fibonacci_fast.cpp

Go to the documentation of this file.

 
#include <cinttypes>
#include <cstdio>
#include <iostream>
 
#define MAX 93
 
uint64_t fib(uint64_t n) {
    static uint64_t f1 = 1,
                    f2 = 1;  // using static keyword will retain the values of
                             // f1 and f2 for the next function call.
 
    if (n <= 2)
        return f2;
    if (n >= 93) {
        std::cerr
            << "Cannot compute for n>93 due to limit of 64-bit integers\n";
        return 0;
    }
 
    uint64_t temp = f2;  // we do not need temp to be static
    f2 += f1;
    f1 = temp;
 
    return f2;
}
 
int main() {
    // Main Function
    for (uint64_t i = 1; i < 93; i++) {
        std::cout << i << " th fibonacci number is " << fib(i) << std::endl;
    }
    return 0;
}