fibr.cpp

来自「经典c++程序的实现」· C++ 代码 · 共 26 行

#include <iostream.h>
#include <stdlib.h>
#include <assert.h>

#include "..\include\book.h"

int Fibr(int n) { // Fibi(n) must fit in a long, so n < 47
  assert((n>0) && (n<47));            // Base case
  if ((n == 1) || (n == 2)) return 1; // Base case
  return Fibr(n-1) + Fibr(n-2);       // Recursive call
}

int main(int argc, char** argv) {
  int n;

  if(argc != 2) {
    cout << "Usage: fibr <n>\n";
    exit(-1);
  }

  n = atoi(argv[1]);

  cout << "Fib(" << n << ") = " << Fibr(n) << "\n";
  return 0;
}