遞歸和非遞歸分別實現求第n個斐波那契數。
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//(1)遞歸的方法:
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
int Fib(int n)
{
if (n == 1 || n == 2)
{
return 1;
}
return Fib(n - 1) + Fib(n - 2);
}
int main()
{
int n = 0;
printf("please input a num:");
scanf("%d", &n);
int num = Fib(n);
printf("%d\n", num);
system("pause");
return 0;
}
//(2)非遞歸的方法:(循環)
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
int Fib(int n)
{
if (n == 1 || n == 2)
{
return 1;
}
int num1 = 1;
int num2 = 1;
int sum = 0;
for (int i = 3; i <= n; ++i)
{
sum = num1 + num2;
num1 = num2;
num2 = sum;
}
return sum;
}
int main()
{
int n = 0;
printf("請輸入要求的斐波那契數列的項數:\n");
scanf("%d", &n);
int num = Fib(n);
printf("%d\n", num);
system("pause");
return 0;
}
編寫一個函數實現n^k,
//(1)非遞歸實現:(n爲整數,不考慮k爲分數,負數)
#define _crt_secure_no_warnings
#include<stdio.h>
#include<stdlib.h>
int factor(int n,int k)
{
int mul = 1;
for (int i = 1; i <= k; ++i)
{
mul = mul*n;
}
return mul;
}
int main()
{
int n = 0;
int k = 0;
printf("請輸入n和k:");
scanf("%d %d", &n,&k);
int num = factor(n,k);
printf("%d\n", num);
system("pause");
return 0;
}
////(2)遞歸實現
#define _CRT_SECURE_NO_WARNINGS//(n爲整數,不考慮k爲分數,負數)
#include<stdio.h>
#include<stdlib.h>
int Factor(int n, int k)
{
if (k == 1)
{
return n*1;
}
else
{
return Factor(n, k-1)*n;
}
return 0;
}
int main()
{
int n = 0;
int k = 0;
printf("請輸入n和k:\n");
scanf("%d %d", &n, &k);
int num = Factor(n, k);
printf("%d\n", num);
system("pause");
return 0;
}
遞歸方式實現打印一個整數的每一位
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
void Factor(int n)
{
int tmp = 0;
if (n > 9)
{
Factor(n / 10);
}
printf("%d\n", n % 10);
}
int main()
{
int n = 0;
printf("請輸入一個數字:\n");
scanf("%d", &n);
Factor(n);
system("pause");
return 0;
}
寫一個遞歸函數DigitSum(n),輸入一個非負整數,返回組成它的數字之和,
例如,調用digitsum(1729),則應該返回1 + 7 + 2 + 9,它的和是19
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
int DigitSum(int n)
{
if (n > 0)
{
return n % 10 + DigitSum(n / 10);
}
return 0;
}
int main()
{
int num = 0;
scanf("%d", &num);
printf("%d\n", DigitSum(num));
system("pause");
return 0;
}
遞歸和非遞歸分別實現求n的階乘
//(遞歸方法:)
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
int Fac(int num)
{
if (num == 1)
{
return 1;
}
if (num > 1)
{
return Fac(num - 1)*num;
}
return 0;
}
int main()
{
int n = 0;
scanf("%d", &n);
int num = Fac(n);
printf("%d\n", num);
system("pause");
return 0;
}
(1)非遞歸方法:
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
int main()
{
int n = 0;
scanf("%d", &n);
int mul = 1;
for (int i = n; i > 0; --i)
{
mul *= i;
}
printf("%d\n", mul);
system("pause");
return 0;
}