{
  "machine": "TM",
  "sigma": [
    "0",
    "1",
    "+"
  ],
  "stackAlpha": [
    "0",
    "1",
    "+",
    "⊔"
  ],
  "states": [
    {
      "id": "s1",
      "x": 150,
      "y": 150,
      "name": "seek +"
    },
    {
      "id": "s2",
      "x": 430,
      "y": 150,
      "name": "b > 0?"
    },
    {
      "id": "s3",
      "x": 710,
      "y": 150,
      "name": "b end"
    },
    {
      "id": "s4",
      "x": 710,
      "y": 350,
      "name": "b −1"
    },
    {
      "id": "s5",
      "x": 430,
      "y": 350,
      "name": "return"
    },
    {
      "id": "s6",
      "x": 150,
      "y": 350,
      "name": "a +1"
    },
    {
      "id": "s7",
      "x": 620,
      "y": 550,
      "name": "erase b"
    },
    {
      "id": "s8",
      "x": 340,
      "y": 550,
      "name": "acc"
    }
  ],
  "startId": "s1",
  "accepts": [
    "s8"
  ],
  "transitions": [
    {
      "id": "t1",
      "from": "s1",
      "to": "s1",
      "symbol": "0",
      "write": "0",
      "dir": "R"
    },
    {
      "id": "t2",
      "from": "s1",
      "to": "s1",
      "symbol": "1",
      "write": "1",
      "dir": "R"
    },
    {
      "id": "t3",
      "from": "s1",
      "to": "s2",
      "symbol": "+",
      "write": "+",
      "dir": "R"
    },
    {
      "id": "t4",
      "from": "s2",
      "to": "s2",
      "symbol": "0",
      "write": "0",
      "dir": "R"
    },
    {
      "id": "t5",
      "from": "s2",
      "to": "s3",
      "symbol": "1",
      "write": "1",
      "dir": "R"
    },
    {
      "id": "t6",
      "from": "s2",
      "to": "s7",
      "symbol": "⊔",
      "write": "⊔",
      "dir": "L"
    },
    {
      "id": "t7",
      "from": "s3",
      "to": "s3",
      "symbol": "0",
      "write": "0",
      "dir": "R"
    },
    {
      "id": "t8",
      "from": "s3",
      "to": "s3",
      "symbol": "1",
      "write": "1",
      "dir": "R"
    },
    {
      "id": "t9",
      "from": "s3",
      "to": "s4",
      "symbol": "⊔",
      "write": "⊔",
      "dir": "L"
    },
    {
      "id": "t10",
      "from": "s4",
      "to": "s4",
      "symbol": "0",
      "write": "1",
      "dir": "L"
    },
    {
      "id": "t11",
      "from": "s4",
      "to": "s5",
      "symbol": "1",
      "write": "0",
      "dir": "L"
    },
    {
      "id": "t12",
      "from": "s5",
      "to": "s5",
      "symbol": "0",
      "write": "0",
      "dir": "L"
    },
    {
      "id": "t13",
      "from": "s5",
      "to": "s5",
      "symbol": "1",
      "write": "1",
      "dir": "L"
    },
    {
      "id": "t14",
      "from": "s5",
      "to": "s6",
      "symbol": "+",
      "write": "+",
      "dir": "L"
    },
    {
      "id": "t15",
      "from": "s6",
      "to": "s6",
      "symbol": "1",
      "write": "0",
      "dir": "L"
    },
    {
      "id": "t16",
      "from": "s6",
      "to": "s1",
      "symbol": "0",
      "write": "1",
      "dir": "R"
    },
    {
      "id": "t17",
      "from": "s7",
      "to": "s7",
      "symbol": "0",
      "write": "⊔",
      "dir": "L"
    },
    {
      "id": "t18",
      "from": "s7",
      "to": "s8",
      "symbol": "+",
      "write": "⊔",
      "dir": "L"
    }
  ],
  "notes": [
    {
      "id": "n1",
      "x": 30,
      "y": 500,
      "color": "blue",
      "anchorStates": [],
      "anchorTransitions": [],
      "text": "Adds a+b in place by transferring one unit at a time: decrement the right number, increment the left, repeat until the right number is all zeros — then erase it and the +. The sum materializes where a used to be."
    },
    {
      "id": "n2",
      "x": 880,
      "y": 150,
      "color": "green",
      "anchorStates": [],
      "anchorTransitions": [],
      "text": "Run 1011+11 and let it play: the highlight pulses around the ring once per transferred unit. A calculator built from a tape and eight states."
    },
    {
      "id": "n3",
      "x": 880,
      "y": 350,
      "color": "orange",
      "anchorStates": [],
      "anchorTransitions": [],
      "text": "The tape has no room left of cell 0, so give the left number a spare leading 0 if it might overflow: 0111+1, not 111+1."
    }
  ],
  "meta": {
    "title": "Binary addition a+b",
    "blurb": "Computes a+b on the tape by transferring one unit per lap: decrement b, increment a, repeat; when b hits zero it is erased and the sum sits where a was.",
    "inputs": [
      {
        "w": "1011+11",
        "expect": "accept",
        "tape": "1110",
        "label": "11+3=14"
      },
      {
        "w": "10+1",
        "expect": "accept",
        "tape": "11",
        "label": "2+1=3"
      },
      {
        "w": "1001+101",
        "expect": "accept",
        "tape": "1110",
        "label": "9+5=14"
      },
      {
        "w": "11",
        "expect": "reject",
        "label": "no +"
      },
      {
        "w": "+11",
        "expect": "reject",
        "label": "no left number"
      }
    ],
    "library": {
      "author": {
        "login": "thethinkmachine"
      },
      "license": "CC-BY-4.0",
      "tags": [
        "showcase",
        "tm"
      ],
      "difficulty": "intermediate"
    }
  },
  "format": "automata-studio/workspace",
  "schema": 1,
  "app": "dev"
}