commit 9ff3ca5bb06c5c72d65c5ebf606cff4167449854 · treybastian.com/advent-of-code

+26 -44

2024/day_03.f90

···

       1
        
       program day_03

     

       2
        
          implicit none

     

       3
       -
          integer ::io, ios, a, b, state, res, cmd_state, digit_state

     

       0
        
       
     

       4
        
          character(len=1) :: c

     

       5
       -
          character(len=10) :: buffer ! buffer to store the number

     

       0
        
       
     

       0
        
       
     

       6
        
          res = 0

     

       7
        
          open(newunit=io, file='./day_03_input.txt', status='old', action='read', access='stream')

     

       8
       -
          state = 0 ! 0 = find command, 1 = find number, 3 = calculate

     

       9
       -
          digit_state = 0 ! 0 = find a, 1 = find b

     

       10
       -
          cmd_state = 0 ! 0 = find m, 1 = find u, 2 = find l 3 = find (

     

       11
        
          buffer = ''

     

       12
        
          do

     

       13
        
             read(io, iostat=ios) c

     

       14
        
             if (ios /= 0) exit

     

       15
        
             select case(state)

     

       16
        
              case (0) ! find command

     

       17
       -
                select case(cmd_state)

     

       18
       -
                 case (0) ! find m

     

       19
       -
                   if (c == 'm') then

     

       20
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                      cmd_state = 1

     

       21
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                   else

     

       22
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                      cmd_state = 0

     

       23
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                   end if

     

       24
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                 case (1) ! find u

     

       25
       -
                   if (c == 'u') then

     

       26
       -
                      cmd_state = 2

     

       27
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                   else

     

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                      cmd_state = 0

     

       29
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                   end if

     

       30
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                 case(2) ! find l

     

       31
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                   if (c == 'l') then

     

       32
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                      cmd_state = 3

     

       33
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                   else

     

       34
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                      cmd_state = 0

     

       35
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                   end if

     

       36
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                 case(3)   ! find (

     

       37
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                   if (c == '(') then

     

       38
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                      state = 1

     

       39
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                      cmd_state = 0

     

       40
       -
                   else

     

       41
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                      cmd_state = 0

     

       42
       -
                   end if

     

       43
       -
                end select

     

       44
        
              case (1) ! find digits

     

       45
        
                select case (iachar(c))

     

       46
        
                 case (48:57) ! 0-9

     

       47
        
                   buffer = trim(buffer) // c

     

       48
        
                 case (44) ! ,

     

       49
       -
                   if (digit_state == 0 .and. len(trim(buffer)) > 0) then

     

       50
        
                      read(buffer, *) a

     

       51
       -
                      print*, 'a: ', a

     

       52
        
                      buffer = ''

     

       53
       -
                      digit_state = 1

     

       54
        
                   else

     

       55
        
                      state = 0 ! invalid

     

       56
       -
                      digit_state = 0

     

       57
        
                      buffer = ''

     

       58
        
                   end if

     

       59
        
                 case (41) ! )

     

       60
       -
                   if(digit_state == 1 .and. len(trim(buffer)) > 0) then

     

       61
        
                      read(buffer, *) b

     

       62
       -
                      print*, 'b: ', b

     

       63
       -
                      state = 3 ! reset state

     

       64
       -
                      digit_state = 0

     

       65
        
                      buffer = ''

     

       66
        
                   else

     

       67
        
                      state = 0

     

       68
       -
                      digit_state = 0

     

       69
        
                      buffer = ''

     

       70
        
                   end if

     

       71
        
                 case default

     

       72
        
                   state = 0

     

       73
       -
                   digit_state = 0

     

       74
        
                   buffer = ''

     

       75
        
                end select

     

       76
        
             end select

     

       77
       -
             if(state == 3) then

     

       78
        
                res = res + (a * b)

     

       79
        
                state = 0

     

       0
        
       
     

       80
        
             end if

     

       81
        
          end do

     

       82
        
          print*, res

     

       83
       -
       end program

···

       1
        
       program day_03

     

       2
        
          implicit none

     

       3
       +
          logical :: find_a

     

       4
       +
          integer ::io, ios, a, b, state, res

     

       5
        
          character(len=1) :: c

     

       6
       +
          character(len=10) :: buffer

     

       7
       +
          character(len=4) :: mul_cmd = 'mul('

     

       8
       +
       

     

       9
        
          res = 0

     

       10
        
          open(newunit=io, file='./day_03_input.txt', status='old', action='read', access='stream')

     

       11
       +
          state = 0 ! 0 = find command, 1 = find number, 2 = calculate

     

       12
       +
          find_a = .true.

     

       0
        
       
     

       13
        
          buffer = ''

     

       14
        
          do

     

       15
        
             read(io, iostat=ios) c

     

       16
        
             if (ios /= 0) exit

     

       17
        
             select case(state)

     

       18
        
              case (0) ! find command

     

       19
       +
                buffer = trim(buffer) // c

     

       20
       +
                if(buffer == mul_cmd) then

     

       21
       +
                   state = 1

     

       22
       +
                   buffer = ''

     

       23
       +
                else if(trim(buffer) /= mul_cmd(1:len(trim(buffer)))) then

     

       24
       +
                   state = 0

     

       25
       +
                   buffer = ''

     

       26
       +
                end if

     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       27
        
              case (1) ! find digits

     

       28
        
                select case (iachar(c))

     

       29
        
                 case (48:57) ! 0-9

     

       30
        
                   buffer = trim(buffer) // c

     

       31
        
                 case (44) ! ,

     

       32
       +
                   if (find_a .and. len(trim(buffer)) > 0) then

     

       33
        
                      read(buffer, *) a

     

       0
        
       
     

       34
        
                      buffer = ''

     

       35
       +
                      find_a = .false.

     

       36
        
                   else

     

       37
        
                      state = 0 ! invalid

     

       38
       +
                      find_a = .true.

     

       39
        
                      buffer = ''

     

       40
        
                   end if

     

       41
        
                 case (41) ! )

     

       42
       +
                   if(.not. find_a .and. len(trim(buffer)) > 0) then

     

       43
        
                      read(buffer, *) b

     

       44
       +
                      state = 2

     

       45
       +
                      find_a = .true.

     

       0
        
       
     

       46
        
                      buffer = ''

     

       47
        
                   else

     

       48
        
                      state = 0

     

       49
       +
                      find_a = .true.

     

       50
        
                      buffer = ''

     

       51
        
                   end if

     

       52
        
                 case default

     

       53
        
                   state = 0

     

       54
       +
                   find_a = .true.

     

       55
        
                   buffer = ''

     

       56
        
                end select

     

       57
        
             end select

     

       58
       +
             if(state == 2) then

     

       59
        
                res = res + (a * b)

     

       60
        
                state = 0

     

       61
       +
                buffer = ''

     

       62
        
             end if

     

       63
        
          end do

     

       64
        
          print*, res

     

       65
       +
       end program day_03