very easy
Test  Status  Code Input and Output 

1  Pass 
n = 1;
f = 1;
assert(isequal(fib(n),f))
a =
1
b =
1
f =
1

2  Pass 
n = 6;
f = 8;
assert(isequal(fib(n),f))
a =
1
b =
1
f =
2
a =
1
b =
2
f =
3
a =
2
b =
3
f =
5
a =
3
b =
5
f =
8
a =
5
b =
8

3  Pass 
n = 10;
f = 55;
assert(isequal(fib(n),f))
a =
1
b =
1
f =
2
a =
1
b =
2
f =
3
a =
2
b =
3
f =
5
a =
3
b =
5
f =
8
a =
5
b =
8
f =
13
a =
8
b =
13
f =
21
a =
13
b =
21
f =
34
a =
21
b =
34
f =
55
a =
34
b =
55

4  Pass 
n = 20;
f = 6765;
assert(isequal(fib(n),f))
a =
1
b =
1
f =
2
a =
1
b =
2
f =
3
a =
2
b =
3
f =
5
a =
3
b =
5
f =
8
a =
5
b =
8
f =
13
a =
8
b =
13
f =
21
a =
13
b =
21
f =
34
a =
21
b =
34
f =
55
a =
34
b =
55
f =
89
a =
55
b =
89
f =
144
a =
89
b =
144
f =
233
a =
144
b =
233
f =
377
a =
233
b =
377
f =
610
a =
377
b =
610
f =
987
a =
610
b =
987
f =
1597
a =
987
b =
1597
f =
2584
a =
1597
b =
2584
f =
4181
a =
2584
b =
4181
f =
6765
a =
4181
b =
6765

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