{
  "schema": "wai.quantum.exercise/1",
  "id": "first-circuit",
  "translations": { "zh-CN": "machine-assisted: to be reviewed by a fluent reader before it is advertised" },
  "title": { "en": "A qubit, a gate, a measurement", "zh-CN": "一个量子比特、一个门、一次测量" },
  "task": {
    "en": "One qubit starts in |0⟩. Add one gate so that measuring it gives 1 every time.",
    "zh-CN": "一个量子比特从 |0⟩ 开始。加一个门，使测量结果每次都是 1。"
  },
  "starter": [
    "OPENQASM 3.0;",
    "include \"stdgates.inc\";",
    "qubit[1] q;",
    "bit[1] c;",
    "// your gate here",
    "c = measure q;"
  ],
  "intent": { "distribution": { "1": 1.0 } },
  "hints": {
    "en": [
      "A measurement of |0⟩ always gives 0. What gate takes |0⟩ to |1⟩?",
      "The gate is the quantum version of a NOT: its name is one letter."
    ],
    "zh-CN": [
      "测量 |0⟩ 总是得到 0。哪个门能把 |0⟩ 变成 |1⟩？",
      "这个门是经典“非”运算的量子版本，名字只有一个字母。"
    ]
  },
  "reference": [
    "OPENQASM 3.0;",
    "include \"stdgates.inc\";",
    "qubit[1] q;",
    "bit[1] c;",
    "x q[0];",
    "c = measure q;"
  ],
  "wrong": [
    {
      "fails": "intent",
      "note": "a Hadamard gives 0 or 1 by chance, not 1 every time",
      "qasm": ["OPENQASM 3.0;", "include \"stdgates.inc\";", "qubit[1] q;", "bit[1] c;", "h q[0];", "c = measure q;"]
    },
    {
      "fails": "refused",
      "note": "a gate the reader does not know",
      "qasm": ["OPENQASM 3.0;", "include \"stdgates.inc\";", "qubit[1] q;", "bit[1] c;", "not q[0];", "c = measure q;"]
    }
  ]
}