microsoft/qdk

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License.

namespace BellState {
    /// # Summary
    /// Operation that generates all bell states for testing with `dump_operation.py`.
    ///
    /// # Input
    /// ## qs
    /// Input qubit register
    ///
    /// ## choice
    /// Bell state to construct.
    /// 0: |Φ+〉(PhiPlus)
    /// 1: |Φ-〉(PhiMinus)
    /// 2: |Ψ+〉(PsiPlus)
    /// 3: |Ψ-〉(PsiMinus)

    operation AllBellStates(qs : Qubit[], choice : Int) : Unit is Ctl + Adj {
        import Std.Convert.*;

        H(qs[0]);
        CNOT(qs[0], qs[1]);

        let bitmask = IntAsBoolArray(choice, 2);
        if bitmask[1] {
            X(qs[1]);
        }

        if bitmask[0] {
            Z(qs[0]);
        }

    }
}