Introduction to Q#

- Quantum Computing Concepts

https://docs.microsoft.com/en-us/quantum/quantum-concepts-1-intro
- Microsoft Q# Coding Contest - Summer 2018 - Warmup
https://codeforces.com/contest/1001
- Microsoft Q# Coding Contest - Summer 2018 - Warmupの問題を解いてみた

https://qiita.com/hatoo@github/items/49b8542029a2100efabf

Transcript

1. Introduction to Q#
   Hiroshi Kurokawa, Dev Group, Mitene
   2018-08-27
   Vantage LT meetup
   

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2. What’s Q#?
   Programming Language

   for Quantum Computing
   

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3. What’s Quantum
   Computing?
   Computing using quantum-
   mechanical phenomena
   

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4. What’s Quantum
   Computing?
   Probabilistic vector and
   matrix with complex numbers
   Computing using quantum-
   mechanical phenomena
   

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5. Qubit
   Bit: 0 or 1
   Qubit: superposition of and
   |0> |1>
   A quibit can be represented as

   

   α|0> + β |1>

   

   where the prob. of |0> and |1>

   is |α|2 and |β|2 respectively
   

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6. Machine state
   Classic computerɿ 0110
   Quantum computerɿ superposition of
   |0> |0> |0> |0>
   |0> |0> |0> |1>
   |0> |0> |1> |0>
   and
   and
   …
   |0> |0> |1> |1>
   and
   

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7. |0> |0> |0‌> |0͏>
   Machine state
   Classic computerɿ 0110
   Quantum computerɿ superposition of
   |0> |0> |0> |1͏>
   |0> |0> |1> |0͏>
   and
   and
   …
   |0> |0> |1> |1͏>
   and
   

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8. |000‌0͏>
   Machine state
   Classic computerɿ 0110
   Quantum computerɿ superposition of
   |0001͏>
   |0010͏>
   and
   and
   …
   |0011͏>
   and
   

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9. Matrix operations
   Hadamard operator: H

   H |0> = 1/√2 ( |0> + |1> ) = |+>

   H |1> = 1/√2 ( |0> - |1> ) = |->
   NOT operator: X

   X |0> = |1>

   X |1> = |0>
   

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10. Problem
    https:/
    /codeforces.com/contest/1001/
    problem/A
    You are given |0> and an integer
    Convert the qubit to
    |+> if the integer is 1
    |-> if the integer is -1
    

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11. Solution
    Remember this:

    H |0> = |+>

    H |1> = |->

    X |0> = |1>
    

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12. Solution
    namespace Solution {
    open Microsoft.Quantum.Primitive;
    open Microsoft.Quantum.Canon;
    operation Solve (q : Qubit, sign : Int) : ()
    {
    body
    {
    // q is set as |0>
    if (sign == 1) {
    H(q);
    } else {
    X(q); // flip q to make it |1>
    H(q);
    }
    }
    }
    }
    

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13. Matrix operations
    CNOT operator

    CNOT( |0> |0> ) = |0> |0>

    CNOT( |0> |1> ) = |0> |1>

    CNOT( |1> |0> ) = |1> |1>

    CNOT( |1> |1> ) = |1> |0>
    

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14. Problem
    https:/
    /codeforces.com/contest/1001/
    problem/B
    You are given |00>
    Convert |00> → 1/√2( |00> + |11>)
    

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15. Solution
    Hint:

    |+> |0> = 1/√2 (|0> + |1>) |0>

    = 1/√2 (|00> + |10>
    Remember CNOT:

    CNOT( |0> |0> ) = |0> |0>

    CNOT( |0> |1> ) = |0> |1>

    CNOT( |1> |0> ) = |1> |1>

    CNOT( |1> |1> ) = |1> |0>
    |11>
    

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16. Solution
    namespace Solution {
    open Microsoft.Quantum.Primitive;
    open Microsoft.Quantum.Canon;
    operation Solve (qs : Qubit[], index : Int) : ()
    {
    body
    {
    let x = qs[0];
    let y = qs[1];
    H(x);
    CNOT(x, y);
    }
    }
    }
    

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17. Reference
    Quantum Computing Concepts

    https:/
    /docs.microsoft.com/en-us/quantum/quantum-
    concepts-1-intro
    Microsoft Q# Coding Contest - Summer 2018 -
    Warmup

    https:/
    /codeforces.com/contest/1001
    Microsoft Q# Coding Contest - Summer 2018 -
    Warmupͷ໰୊Λղ͍ͯΈͨ

    https:/
    /qiita.com/hatoo@github/items/
    49b8542029a2100efabf
    

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