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FlipEndian.sol

pragma solidity ^0.4.19;
contract FlipEndian {

    function flip32_1(bytes32 a) public constant returns (bytes32 b){
        assembly {
            0
            and(div(a, 0x100000000000000000000000000000000000000000000000000000000000000), 0xFF)
            or
            and(div(a, 0x10000000000000000000000000000000000000000000000000000000000), 0xFF00)
            or
            and(div(a, 0x1000000000000000000000000000000000000000000000000000000), 0xFF0000)
            or
            and(div(a, 0x100000000000000000000000000000000000000000000000000), 0xFF000000)
            or
            and(div(a, 0x10000000000000000000000000000000000000000000000), 0xFF00000000)
            or
            and(div(a, 0x1000000000000000000000000000000000000000000), 0xFF0000000000)
            or
            and(div(a, 0x100000000000000000000000000000000000000), 0xFF000000000000)
            or
            and(div(a, 0x10000000000000000000000000000000000), 0xFF00000000000000)
            or
            and(div(a, 0x1000000000000000000000000000000), 0xFF0000000000000000)
            or
            and(div(a, 0x100000000000000000000000000), 0xFF000000000000000000)
            or
            and(div(a, 0x10000000000000000000000), 0xFF00000000000000000000)
            or
            and(div(a, 0x1000000000000000000), 0xFF0000000000000000000000)
            or
            and(div(a, 0x100000000000000), 0xFF000000000000000000000000)
            or
            and(div(a, 0x10000000000), 0xFF00000000000000000000000000)
            or
            and(div(a, 0x1000000), 0xFF0000000000000000000000000000)
            or
            and(div(a, 0x100), 0xFF000000000000000000000000000000)
            or
            =: b
            a := mul(a, 0x100000000000000000000000000000000)
            0
            and(div(a, 0x100000000000000000000000000000000000000000000000000000000000000), 0xFF)
            or
            and(div(a, 0x10000000000000000000000000000000000000000000000000000000000), 0xFF00)
            or
            and(div(a, 0x1000000000000000000000000000000000000000000000000000000), 0xFF0000)
            or
            and(div(a, 0x100000000000000000000000000000000000000000000000000), 0xFF000000)
            or
            and(div(a, 0x10000000000000000000000000000000000000000000000), 0xFF00000000)
            or
            and(div(a, 0x1000000000000000000000000000000000000000000), 0xFF0000000000)
            or
            and(div(a, 0x100000000000000000000000000000000000000), 0xFF000000000000)
            or
            and(div(a, 0x10000000000000000000000000000000000), 0xFF00000000000000)
            or
            and(div(a, 0x1000000000000000000000000000000), 0xFF0000000000000000)
            or
            and(div(a, 0x100000000000000000000000000), 0xFF000000000000000000)
            or
            and(div(a, 0x10000000000000000000000), 0xFF00000000000000000000)
            or
            and(div(a, 0x1000000000000000000), 0xFF0000000000000000000000)
            or
            and(div(a, 0x100000000000000), 0xFF000000000000000000000000)
            or
            and(div(a, 0x10000000000), 0xFF00000000000000000000000000)
            or
            and(div(a, 0x1000000), 0xFF0000000000000000000000000000)
            or
            and(div(a, 0x100), 0xFF000000000000000000000000000000)
           or
           and(div(a, 0x1), 0xFF000000000000000000000000000000)
            or
            0x100000000000000000000000000000000
            mul
            b
            or
            =: b
        }
        return b;
    }
}