day15/computer.sh

   1 #!/bin/bash
   2
   3 declare -a data
   4
   5 get_value() {
   6     local -n da=$1
   7     local index=$2
   8
   9     if [ $index -lt 0 ]; then
  10         echo "Index negative, give up!"
  11         exit 2
  12     fi
  13
  14     if ! [ ${da[$index]+a} ]; then
  15         da[$index]=0
  16     fi
  17
  18     declare -g __comp_value="${da[$index]}"
  19 }
  20
  21 get_param() {
  22     local -n dap=$1
  23     local pos=$2
  24     local mode=$3
  25     local relative_base=$4
  26
  27     get_param_loc dap $pos $mode $relative_base
  28     loc=$__comp_param_loc
  29
  30     get_value dap $loc
  31 }
  32
  33 get_param_loc() {
  34     local -n dapl=$1
  35     local pos=$2
  36     local mode=$3
  37     local relative_base=$4
  38
  39     case $mode in
  40         0)
  41             get_value dapl $pos
  42             declare -g __comp_param_loc=$__comp_value
  43             ;;
  44         1)
  45             declare -g __comp_param_loc=$pos
  46             ;;
  47         2)
  48             get_value dapl $pos
  49             move_by=$__comp_value
  50             declare -g __comp_param_loc=$((relative_base+$move_by))
  51             ;;
  52         *)
  53             echo "Unknown parameter mode: $mode"
  54             exit 2
  55             ;;
  56     esac
  57 }
  58
  59 run_program() {
  60     local -n od=$1
  61     local relative_base=0
  62     data=("${od[@]}")
  63     pos=0
  64     declare -a immediate
  65     while [ $pos -le ${#data[@]} ]; do
  66         # first, printf the value to 5 digits
  67         instruction=$(printf "%05d" ${data[$pos]})
  68         for (( a=0; a<3; a++ )); do
  69             immediate[$((3-a))]=${instruction:$a:1}
  70         done
  71         instruction=${instruction:3}
  72         param_count=3
  73         echo -n $'\r'"    "$'\r'$instruction >&2
  74         case $instruction in
  75             01|02)
  76                 # 01 - add, 02 multiply
  77                 symbol="+"
  78                 if [ $instruction == "02" ]; then
  79                     symbol="*"
  80                 fi
  81                 get_param data $((pos+1)) ${immediate[1]} $relative_base
  82                 val1=$__comp_value
  83                 get_param data $((pos+2)) ${immediate[2]} $relative_base
  84                 val2=$__comp_value
  85                 get_param_loc data $((pos+3)) ${immediate[3]} $relative_base
  86                 res_loc=$__comp_param_loc
  87                 data[$res_loc]=$(($val1 $symbol $val2))
  88                 ;;
  89             03)
  90                 # 03 - read input
  91                 echo -n $'\r'"    "$'\r' >&2
  92                 echo "input: "
  93                 read input
  94                 input=${input//\n/}
  95                 input=${input//\r/}
  96                 echo >&2
  97                 echo "$instruction: '$input'" >&2
  98                 echo >&2
  99                 get_param_loc data $((pos+1)) ${immediate[1]} $relative_base
 100                 res_loc=$__comp_param_loc
 101                 data[$res_loc]=$input
 102                 param_count=1
 103                 ;;
 104             04)
 105                 # 04 - output
 106                 get_param data $((pos+1)) ${immediate[1]} $relative_base
 107                 val=$__comp_value
 108                 echo -n $'\r'"    "$'\r' >&2
 109                 echo $val
 110                 param_count=1
 111                 ;;
 112             05|06)
 113                 # 05 - jump-if-true, 06 - jump-if-false
 114                 get_param data $((pos+1)) ${immediate[1]} $relative_base
 115                 val=$__comp_value
 116                 get_param data $((pos+2)) ${immediate[2]} $relative_base
 117                 jumpto=$__comp_value
 118                 param_count=2
 119                 if ( [ $val -ne 0 ] && [ "$instruction" == "05" ] ) ||
 120                     ( [ $val -eq 0 ] && [ "$instruction" == "06" ] ); then
 121                     pos=$jumpto
 122                     continue
 123                 fi
 124                 ;;
 125             07|08)
 126                 # 07 - is less than, 08 - is equal
 127                 get_param data $((pos+1)) ${immediate[1]} $relative_base
 128                 val1=$__comp_value
 129                 get_param data $((pos+2)) ${immediate[2]} $relative_base
 130                 val2=$__comp_value
 131                 echo >&2
 132                 echo "$instruction: '$val1' '$val2'" >&2
 133                 echo >&2
 134                 get_param_loc data $((pos+3)) ${immediate[3]} $relative_base
 135                 res_pos=$__comp_param_loc
 136                 data[$res_pos]=0
 137                 if [ "$instruction" == "07" ]; then
 138                     if [ $val1 -lt $val2 ]; then
 139                         data[$res_pos]=1
 140                     fi
 141                 else
 142                     if [ $val1 -eq $val2 ]; then
 143                         data[$res_pos]=1
 144                     fi
 145                 fi
 146                 ;;
 147             09)
 148                 # adjust relative base
 149                 param_count=1
 150                 get_param data $((pos+1)) ${immediate[1]} $relative_base
 151                 val=$__comp_value
 152                 relative_base=$((relative_base+$val))
 153                 ;;
 154             99)
 155                 break
 156                 ;;
 157             *)
 158                 echo "Invalid opcode: $instruction at position $pos"
 159                 exit 1
 160                 ;;
 161         esac
 162         pos=$(($pos+$param_count+1))
 163     done
 164     echo -n $'\r'"    "$'\r' >&2
 165 }
 166