### Directory Structure

All the source and header files for the MQ solver are under lib/.

Examples to use this library are under samples/.

Testing programs/scripts are under tests/.



### The Primary API Entry Point of This Library

The main function "int exfes(...)" to solve MQ is declared in "exfes.h".

        int exfes(uint32_t numFixedVariables,
                  uint32_t numVariables,
                  uint32_t numEquations,
                  uint64_t startPointHigh,
                  uint64_t startPointLow,
                  const uint8_t *coefficientsMatrix,
                  bool (*shouldAbortNow)(void),
                  uint64_t *solutionHigh,
                  uint64_t *solutionLow);

The tuple (numFixedVariables, numVariables, numEquations) is the parameter for
the MQ system.  For example: (0, 56, 48), (1, 64, 56), (9, 72, 64), (17, 80,
72).

The pair (startPointHigh, startPointLow) represents the start point of the
solving process.  You may use random numbers.

The variable (coefficientsMatrix) represents the array of coefficients in the
MQ system.  Each array element must be 0 or 1.

The variable (shouldAbortNow) is a function pointer provided by the user.  The
solver will call this function during the solving process, and abort if this
function returns true.  User should implement this function to check if some
other node or thread has already found a solution.

The pair (solutionHigh, solutionLow) represents the solution buffer.  If the
solver finds a solution, the solution will be written here.



### Return Values

Returning 0 means the solver found a solution, and wrote the solution into the
solution buffer.

Returning -1 means the solver searched all possibilities but no solution was
found.

Returning -2 means the solver was interrupted by the shouldAbortNow function.

Returning -3 means the some input parameters are invalid.

Returning -4 means a dynamic memory allocation failure; this rarely happens;
the caller could retry the computation.



### How to Build

Simply "make" shall build all executables.