Lecture "Recursion", exercise 2

[essepuntato]

Define a recursive function def fib(n) that implements the algorithm to find the n^the Fibonacci number. In particular, if n is less than or equal to 0, then 0 is returned as a result. Otherwise, if n is equal to 1, then 1 is returned. Otherwise, return the sum of the same function called with n-1 and n-2 as input. Please accompany the function with the related test case.

[martasoricetti]

[11051620]

def fib(n): if n <= 0: return 0 if n == 1: return 1

else:
    return fib(n - 1) + fib(n - 2)

[ManueleVeggi]

def test_fib(n, expected):
    result = fib(n)
    if result == expected:
        return True
    else:
        return False

def fib(n):
    if n <= 0:
        return 0
    elif n == 1:
        return 1
    else:
        return fib(n-1)+fib(n-2)

print(test_fib(-1, 0)) 
print(test_fib(0, 0))
print(test_fib(1, 1))
print(test_fib(5, 5))
print(test_fib(10,55))

The output is:

True
True
True
True
True

[Postitisnt]

def fib(n):
    if n <= 0:
        return 0
    elif n == 1:
        return 1
    else:
        return fib(n-1) + fib(n-2)

def test_fib (n, expected):
    if expected == fib(n):
        return True
    else:
        return False

testF_1 = test_fib(7, 13)
testF_2 = test_fib(-2, 0)
testF_3 = test_fib(1, 1)
testF_4 = test_fib(0, 0)

[tommasobattisti]

def test_fib(n, expected):
    result = fib(n)
    if result == expected:
        return True
    else:
        return False

def fib(n):
    if n <= 0:
        return 0
    elif n == 1:
        return 1
    else:
        return fib(n -1) + fib(n-2)

print(test_fib(-1, 0))
print(test_fib(0, 0))
print(test_fib(1, 1))
print(test_fib(2, 1))
print(test_fib(7, 13))

[giorgimariachiara]

def test_fib(n, expected):
    result = fib(n)
    if expected == result:
        return True

def fib(n):
    if n <= 0:
        return 0
    elif n == 1:
        return 1
    else:
        return fib(n-1) + fib(n-2)

print(test_fib(3, 2))

[CarmenSantaniello]

def test_fib_n(n, expected):
    result = fib(n)
    if result == expected:
        return True
    else:
        return False

def fib(n):
    if n <= 0:
        return 0
    elif n == 1:
        return 1
    else:
        return fib(n-1) + fib(n-2)

print(test_fib_n(4, 3))
print(test_fib_n(8, 21))
print(fib(4))
print(fib(8))

It returns:

True
True
3
21

[OrsolaMBorrini]

def test_fib(n,expected):
    result = fib(n)
    if result == expected:
        return True
    else:
        return False

def fib(n):
    if n<=0:
        return 0
    elif n==1:
        return 1
    else:
        return fib(n-1)+fib(n-2)

print(test_fib(0,0)) #True
print(test_fib(1,1)) #True
print(test_fib(2,1)) #True
print(test_fib(12,144)) #True

[AmeliaLamargese]

def test_fib(n, expected):
    result = fib(n)
    if result == expected:
        return True
    else:
        return False

def fib(n):
    if n <= 0:
        return 0
    elif n == 1:
        return 1
    else:
        return fib(n-1) + fib(n-2)

print(test_fib(-2, 0))
print(test_fib(0, 0))
print(test_fib(1, 1))
print(test_fib(2, 1))
print(test_fib(5, 5))  

[elizastuglik]

def test_fib(n, expected):
    result = fib(n)
    if expected == result:
        return True

def fib(n):
    if n <= 0:
        return 0
    elif n == 1:
        return 1
    else:
        return fib(n-1) + fib(n-2)

print(test_fib(7, 13))

[SaraVell1]

[RebeccaJillianBeattie]

[olgagolgan]

[Bianca-LM]

def test_fib(n, expected): 
    result = fib(n)
    if expected == result: 
        return True
    else: 
        return False

def fib(n): 
    if n <= 0: 
        return 0
    if n == 1: 
        return 1
    else: 
        return fib(n-1)+fib(n-2)

print(test_fib(7,13))
print(test_fib(4,3))

[MaddaGh]

resluts are 13 121393 True True

[NoraPs]

[katya-avem]

[AnastasiyaSopyryaeva]

Input

#Defining test function

def test_fib(n, expected):
    result = fib(n)
    if expected == result:
        return True
    else:
        return False

#Function code
def fib(n):
    if n <= 0:
        return 0
    elif n == 1:
        return 1
    else:
        return fib(n-1) + fib(n-2)

#print
print(test_fib(7, 13))
print(test_fib(9, 34))
print(test_fib(1, 0))

Output True True False

[francescabudel]

def fib(n): 
    if n <= 0: 
        return 0 
    elif n == 1: 
        return 1 
    else: 
        return fib(n-1) + fib(n-2)

print(fib(7))
print(fib(1)) 
print(fib(0))
print(fib(9)) 

13
1
0
34

[angstigone]

[chloeppd]

def test_fib(n,expected):
    result=fib(n)
    if result == expected:
        return True
    else:
        return False

def fib(n):
    if n<=0:
        return 0

    elif n==1:
        return 1

    else:
        return fib(n-1)+fib(n-2)

print (test_fib(-3,0))
print(test_fib(1,1))
print(test_fib(7,13))

[sanyuezoe]

def test_fib(n, expected):
    result = fib(n)
    if expected == result:
        return True
    else:
        return False

def fib(n):
    if n <= 0:
        return 0
    elif n <= 2:
        return 1
    else:
        return fib(n-1)+fib(n-2)

print(test_fib(0, 0))
print(test_fib(2, 1))
print(test_fib(7, 13))

Output

True
True
True

[ghasempouri1984]

def test_fib(n, expected):
    result = fib(n)
    if result == expected:
        return True
    else:
        return False

def fib(n):
    f = [0, 1]

    for i in range(2, n + 1):
        f.append(f[i - 1] + f[i - 2])
    return f[n]

print(test_fib(0, 0))
print(test_fib(-2, 0))
print(test_fib(1, 1))
print(test_fib(2, 1))
print(test_fib(9, 34))

[essepuntato]

Hi all, just a couple of notes:

• @ghasempouri1984 it should be a recursive function
• the tests are important (i.e. they should be provided) and they must pass
• please remember to format your code appropriately

[teragramgius]

[ahsanv101]

result: True True True True True