为什么我的代码输出中的数字与预期输出结果(粘贴在最后)之间存在差异?
我经历了这些与递归调用次数计算相关的问题:
我无法对我的问题形成正确的答案或解决方案。
我什至尝试通过在 for 循环之后的 main() 函数中或在函数定义中写入 call_count = 0;
来重新初始化计数(如第二个链接的答案中所建议的那样)上面)但是,它没有工作或没有给我预期的输出。
我在下方粘贴了我的代码及其输出,在我的代码输出下方粘贴了预期输出。
#include <iostream>
#include "math.h"
#include <iomanip>
using namespace std;
int call_count = 0;
int fibo(int n)
{
call_count+=1;
if(n<=2)
{
return 1;
}
else {
//call_count += 1;
return fibo(n-1) + fibo(n-2);
}
return n;
}
int main()
{
int num;
cout<<"\nenter the number of integers to be printed in the fibonacci series\n";
cin>>num;
cout<<"\nfibonacci series for first "<<num<<" numbers is\n";
cout<<"\n\nSerial Number\t"<<"FIBO_NUMBER\t"<<" NO_OF_CALLS MADE\n\n";
for(int i=1;i<=num;i++)
{
cout<<endl<<i<<"th number\t "<<fibo(i)<<"\t\t"<<call_count<<" calls\n";
}
cout<<endl<<"\n the total number of recursive calls made were "<<call_count<<endl<<endl;
system("pause");
return 0;
}
我的代码的输出:
enter the number of integers to be printed in the fibonacci series
15
fibonacci series for first 15 numbers is
Serial Number FIBO_NUMBER NO_OF_CALLS MADE
1th number 1 0 calls
2th number 1 1 calls
3th number 2 2 calls
4th number 3 5 calls
5th number 5 10 calls
6th number 8 19 calls
7th number 13 34 calls
8th number 21 59 calls
9th number 34 100 calls
10th number 55 167 calls
11th number 89 276 calls
12th number 144 453 calls
13th number 233 740 calls
14th number 377 1205 calls
15th number 610 1958 calls
the total number of recursive calls made were 3177
Press any key to continue . . .
而预期的输出数字如下:
1 th integer of fibonacci series is 1 and it needed 0 recursive calls
2 th integer of fibonacci series is 1 and it needed 0 recursive calls
3 th integer of fibonacci series is 2 and it needed 2 recursive calls
4 th integer of fibonacci series is 3 and it needed 4 recursive calls
5 th integer of fibonacci series is 5 and it needed 8 recursive calls
6 th integer of fibonacci series is 8 and it needed 14 recursive calls
7 th integer of fibonacci series is 13 and it needed 24 recursive calls
8 th integer of fibonacci series is 21 and it needed 40 recursive calls
9 th integer of fibonacci series is 34 and it needed 66 recursive calls
10 th integer of fibonacci series is 55 and it needed 108 recursive calls
11 th integer of fibonacci series is 89 and it needed 176 recursive calls
12 th integer of fibonacci series is 144 and it needed 286 recursive calls
13 th integer of fibonacci series is 233 and it needed 464 recursive calls
14 th integer of fibonacci series is 377 and it needed 752 recursive calls
15 th integer of fibonacci series is 610 and it needed 1218 recursive calls
Press any key to continue . . .
如何解决这种不匹配?
最佳答案
在调用 fibo() 方法之前将 call_count 重置为零。
#include <iostream>
#include "math.h"
#include <iomanip>
using namespace std;
int call_count = 0;
int fibo(int n)
{
call_count+=1;
if(n<=2)
{
return 1;
}
else {
//call_count += 1;
return fibo(n-1) + fibo(n-2);
}
return n;
}
int main()
{
int num;
cout<<"\nenter the number of integers to be printed in the fibonacci series\n";
cin>>num;
cout<<"\nfibonacci series for first "<<num<<" numbers is\n";
cout<<"\n\nSerial Number\t"<<"FIBO_NUMBER\t"<<" NO_OF_CALLS MADE\n\n";
for(int i=1;i<=num;i++)
{
call_count = 0;
cout<<endl<<i<<"th number\t "<<fibo(i)<<"\t\t"<<call_count<<" calls\n";
}
cout<<endl<<"\n the total number of recursive calls made were " <<call_count<<endl<<endl;
system("pause");
return 0;
}
关于c++ - 每个斐波那契数的递归调用次数,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/32751005/