// 递归计算斐波那契数
long fibonacci_recursion( int n )
{
if( n <= 2 )
return 1;
return fibonacci_recursion(n-1) + fibonacci_recursion(n-2);
}
int main(){
int N = 45;
// 递归消耗的时间
clock_t recursion_start_time = clock();
long result_recursion = fibonacci_recursion(N);
clock_t recursion_end_time = clock();
// 迭代消耗的时间
clock_t iteration_start_time = clock();
long result_iteration = fibonacci_iteration(N);
clock_t iteration_end_time = clock();
// 输出递归消耗的时间
printf("Result of recursion: %ld \nTime: %fseconds",
fibonacci_recursion(N),
(double)(recursion_end_time-recursion_start_time)/CLOCKS_PER_SEC
);
printf("\n-----------------------\n");
// 输出迭代消耗的时间
printf("Result of iteration: %ld \nTime: %fseconds",
fibonacci_iteration(N),
(double)(iteration_end_time-iteration_start_time)/CLOCKS_PER_SEC
);
return 0;
}
//利用递归实现斐波拉契数列
int fibonacci_recursion(int n)
{
if (n < 2) {
return n;
} else {
return fibonacci_recursion(n - 1) + fibonacci_recursion(n - 2);
}
}
int recursion::fibonacci_recursion(int i, int& num_rec) {
if (i == 0) {
return 0;
}
if (i == 1) {
return 1;
}
return fibonacci_recursion(i - 2, ++num_rec) + fibonacci_recursion(i - 1, ++num_rec);
}
int Fibonacci::fibonacci_recursion(int num) {
if(num==0 || num==1) {
return num;
}
return fibonacci_recursion(num-1)+fibonacci_recursion(num-2);
}