I am interested in an iterative algorithm for Fibonacci numbers, so I found the formula on wiki...it looks straight forward so I tried it in Python...it doesn't have a problem compiling and formula looks right...not sure why its giving the wrong output...did I not implement it right ?
def fib (n): 
    if( n == 0):
        return 0
    else:
        x = 0
        y = 1
        for i in range(1,n):
            z = (x + y)
            x = y
            y = z
            return y
for i in range(10):
    print (fib(i))
output
0
None
1
1
1
1
1
1
 
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
    