day7 aoc 2019.js

const permutations = arr => {
  let perms = [];

  for (let i = 0; i < arr.length; i++) {
    let rest = permutations(arr.slice(0, i).concat(arr.slice(i + 1)));

    if(!rest.length) {
      perms.push([arr[i]])
      continue;
    }
    
    for(let j = 0; j < rest.length; j++) {
      perms.push([arr[i]].concat(rest[j]))
    }
  }
  return perms;
}

const amplifier = phase => {
  const program = new Int32Array(`3,8,1001,8,10,8,105,1,0,0,21,34,47,72,81,102,183,264,345,426,99999,3,9,102,5,9,9,1001,9,3,9,4,9,99,3,9,101,4,9,9,1002,9,3,9,4,9,99,3,9,102,3,9,9,101,2,9,9,102,5,9,9,1001,9,3,9,1002,9,4,9,4,9,99,3,9,101,5,9,9,4,9,99,3,9,101,3,9,9,1002,9,5,9,101,4,9,9,102,2,9,9,4,9,99,3,9,1002,9,2,9,4,9,3,9,101,2,9,9,4,9,3,9,102,2,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1001,9,1,9,4,9,3,9,1001,9,1,9,4,9,3,9,1001,9,2,9,4,9,3,9,101,1,9,9,4,9,99,3,9,101,1,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,102,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,102,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,1001,9,2,9,4,9,3,9,101,2,9,9,4,9,99,3,9,101,1,9,9,4,9,3,9,101,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,101,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,101,1,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,1001,9,1,9,4,9,3,9,102,2,9,9,4,9,3,9,1002,9,2,9,4,9,99,3,9,1001,9,2,9,4,9,3,9,101,1,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,102,2,9,9,4,9,3,9,101,1,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,1001,9,1,9,4,9,3,9,101,2,9,9,4,9,3,9,101,2,9,9,4,9,3,9,102,2,9,9,4,9,99,3,9,102,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,101,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,102,2,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,1001,9,1,9,4,9,99`.split(/,/g).map(m => parseInt(m)));

  let pc = 0;
  let results = [];
  let inputIndex = 0;

  const mode = {
    1: 0,
    2: 0,
    3: 0
  }
  
  const getValue = (d) => (mode[d] ? program[pc + (d - 1)] : program[program[pc + (d - 1)]]);

  const getPointer = (d) => (mode[d] ? pc + (d - 1) : program[pc + (d - 1)]);


  const modes = () => {
    return `p1:${(mode[1] ? 'i' : 'p')} p2:${(mode[2] ? 'i' : 'p')} p3:${(mode[3] ? 'i' : 'p')}`
  }

  let usedPhase = false;

  return (input) => {

    while(!window.stopNowPlease){
      let inst = program[pc++];

      mode[3] = ~~(inst / 10000)
      let op = inst - (mode[3] * 10000);
      mode[2] = ~~(op / 1000);
      op = op - (mode[2] * 1000);
      mode[1] = ~~(op / 100)
      op = op - (mode[1] * 100);

      switch(op) {
        case 1: {
          let a = getValue(1);
          let b = getValue(2);
          program[getPointer(3)] = a + b;
          //results.push(`add ${mode[1] ? '' : '$'}${program[pc]}(${a}) ${mode[2] ? '' : '$'}${program[pc+1]}(${b}) $${program[pc+2]}(${getValue(3)})`);
          pc += 3;
          break;
        }
        case 2: {
          let a = getValue(1);
          let b = getValue(2);
          program[getPointer(3)] = a * b;
          //results.push(`mul ${mode[1] ? '' : '$'}${program[pc]}(${a}) ${mode[2] ? '' : '$'}${program[pc+1]}(${b}) $${program[pc+2]}(${getValue(3)})`);
          pc += 3;
          break;
        }
        case 3: {
          let i;
          if (!usedPhase) {
            i = phase;
            usedPhase = !usedPhase;
          } else {
            i = input;
          }
          program[getPointer(1)] = i;
          //results.push(`set ${i} ${mode[1] ? '' : '$'}${program[pc]}(${getValue(1)}) `);
          pc += 1
          break;
        }
        case 4: {
          let r = getValue(1);
          //results.push(`get ${mode[1] ? '' : '$'}${program[pc]}(${r}) ${input}`)
          pc++;
          return r;
          break;
        }
        case 5: {
          if (getValue(1)) {
            pc = getValue(2);
          } else {
            pc += 2;
          }
          //results.push(`jit ${mode[1] ? '' : '$'}${program[pc]}(${getValue(1)}) $${program[pc+1]}(${getValue(2)})`);
          break;
        }
        case 6: {
          //results.push(`jif ${mode[1] ? '' : '$'}${program[pc]}(${getValue(1)}) $${program[pc+1]}(${getValue(2)})`);
          if (!getValue(1)) {
            pc = getValue(2);
          } else {
            pc += 2;
          }
          break;
        }
        case 7: {
          let c = getPointer(3);
          if (getValue(1) < getValue(2)) {
            program[c] = 1;
          } else {
            program[c] = 0;
          }
          //results.push(`jlt ${mode[1] ? '' : '$'}${program[pc]}(${getValue(1)}) ${mode[2] ? '' : '$'}${program[pc+1]}(${getValue(2)}) $${program[pc+2]}(${getValue(3)})`);
          pc += 3;
          break;
        }
        case 8: {
          //results.push(`jeq ${mode[1] ? '' : '$'}${program[pc]}(${getValue(1)}) ${mode[2] ? '' : '$'}${program[pc+1]}(${getValue(2)}) $${program[pc+2]}(${getValue(3)})`);
          let c = getPointer(3);
          if (getValue(1) === getValue(2)) {
            program[c] = 1;
          } else {
            program[c] = 0;
          }
          pc += 3;
          break;
        }
        case 99: {
          return null
        }
        default: {
          debugger;
          break;
        }
      }
    }
    return null;
  }
}

const run () => {
  const result = permutations([5, 6, 7, 8, 9]).map(perm => {
    let amps = [
        amplifier(perm[0]),
        amplifier(perm[1]),
        amplifier(perm[2]),
        amplifier(perm[3]),
        amplifier(perm[4]),
    ];
    let i = 0;
    let v = 0;
    let done = false;

    while(!done) {
      let r = amps[i](v);
      if (r !== null) {
      v = r;
      i = (i + 1) % amps.length;
      } else {
        done = true;
        return {
          score: v,
          perm
        }
      }
    }
  }).sort((a, b) => a.score - b.score);
  return result[result.length -1];
}