AOC2019day2

2.sh

#!/bin/bash

set -eu

IFS=, read -r -a program

for noun in $(seq 0 99); do
  for verb in $(seq 0 99); do
    program[1]=$noun
    program[2]=$verb
    ram=("${program[@]}")
    pc=0
    while true; do
      opcode=${ram[$pc]}
      case $opcode in
        1)
          src1=${ram[$((pc+1))]}
          src2=${ram[$((pc+2))]}
          dest=${ram[$((pc+3))]}
          ram[$dest]=$((ram[src1] + ram[src2]))
          pc=$((pc+4))
        ;;
        2)
          src1=${ram[$((pc+1))]}
          src2=${ram[$((pc+2))]}
          dest=${ram[$((pc+3))]}
          ram[$dest]=$((ram[src1] * ram[src2]))
          pc=$((pc+4))
        ;;
        99)
          break
        ;;
      esac
    done

    result=${ram[0]}
    if [ "$result" = 19690720 ]; then
      echo "100 * ${program[1]} * ${program[2]} = $((100 * program[1] + program[2]))"
      exit
    fi
  done
done