Help with error

#1

code : https://ide.codingblocks.com/s/454778

question: fibo using matrix exponentiation

not getting an output

#2

you are mixing 0 based indexing and 1 based indexing

you declare vector which is 0 based index
but why multiplying you use 1 based indexing

#3


fixed it in line 62, is it an issue somewhere else too? I guess it is because of vector T so I’m thinking inserting 0’s in the first row and not using that row

#4

but only inserting 1 row will not solve the problem
as columns are also messed up

best is to use 0 based indexing always in the whole code

#5


getting wrong values

#6

i think you shared a wrong code

#7
#8

this is the correct one, indexing is not correct in the multiplication function but fixing it still gives the wrong answer

#9

image
this is correct one

Modified code

#10

one issuse with this code is that the indexing of the term is 1 based for example for input 5 it gives answer as 3 and not 5, one solution is that I can manually increment the input by 1, but I saw someone else’s code https://ide.codingblocks.com/s/455099 and it looks the same as mine but gives the desired output(0, based indexing)

#11

it should be 1 based
as it is for user
user will consider first term as 1 not as 0

#12

but the test cases won’t pass that way

#13

then just pass n-1 from main()
to pass testcases

#14

can you please explain why this is giving answer with 0 based indexing

#15

image
make these changes

  1. change the T matrix
  2. after multiplying T and F we get matrix of 2X1
    whose second element will be the ans so to calculate that
    use A[1][i]
#16

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