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Homework 5Homework 5

利用遞迴及非遞迴方式撰寫利用遞迴及非遞迴方式撰寫 FibonacciFibonacci 的的程式。程式。 UserUser輸入輸入 nn值，計算出值，計算出 Fib(n)Fib(n) Fib(n) = Fib(n-1) + Fib(n-2)Fib(n) = Fib(n-1) + Fib(n-2) Fib(0) = 0, Fib(1) = 1Fib(0) = 0, Fib(1) = 1 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, …0, 1, 1, 2, 3, 5, 8, 13, 21, 34, …

Fib(n) = Fib(n-1) + Fib(n-2)Fib(n) = Fib(n-1) + Fib(n-2)Fib(0) = 0, Fib(1) = 1Fib(0) = 0, Fib(1) = 10, 1, 1, 2, 3, 5, 8, 13, 21, 34, 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, ……

int fib(int n){ if(n<=0) return 0; else if(n==1) return 1; else return fib(n-1)+fib(n-2);}

Fib(n) = Fib(n-1) + Fib(n-2)Fib(n) = Fib(n-1) + Fib(n-2)Fib(0) = 0, Fib(1) = 1Fib(0) = 0, Fib(1) = 10, 1, 1, 2, 3, 5, 8, 13, 21, 34, 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, ……

int fib(int n){ if(n<=0) return 0; else if(n==1) return 1; else return fib(n-1)+fib(n-2);}

int fib(int n){ int sum=0, a=0, b=1; for(int i=0; i<n-1; i++) { sum=a+b; b=sum; a=b; } return sum;}