text: 'use strict';
  
  var isInteger = require('../../utils/number').isInteger;
  
  function factory (type, config, load, typed) {
    
    var matrix = load(require('../../type/matrix/function/matrix'));
  
    var algorithm02 = load(require('../../type/matrix/utils/algorithm02'));
    var algorithm06 = load(require('../../type/matrix/utils/algorithm06'));
    var algorithm11 = load(require('../../type/matrix/utils/algorithm11'));
    var algorithm13 = load(require('../../type/matrix/utils/algorithm13'));
    var algorithm14 = load(require('../../type/matrix/utils/algorithm14'));
  
    /**
     * Calculate the least common multiple for two or more values or arrays.
     *
     * lcm is defined as:
     *
     *     lcm(a, b) = abs(a * b) / gcd(a, b)
     *
     * For matrices, the function is evaluated element wise.
     *
     * Syntax:
     *
     *    math.lcm(a, b)
     *    math.lcm(a, b, c, ...)
     *
     * Examples:
     *
     *    math.lcm(4, 6);               // returns 12
     *    math.lcm(6, 21);              // returns 42
     *    math.lcm(6, 21, 5);           // returns 210
     *
     *    math.lcm([4, 6], [6, 21]);    // returns [12, 42]
     *
     * See also:
     *
     *    gcd, xgcd
     *
     * @param {... number | BigNumber | Array | Matrix} args  Two or more integer numbers
     * @return {number | BigNumber | Array | Matrix}                           The least common multiple
     */
    var lcm = typed('lcm', {
      'number, number': _lcm,
  
      'BigNumber, BigNumber': _lcmBigNumber,
  
      // TODO: implement support for Fraction
  
      'Matrix, Matrix': function (x, y) {
        // result
        var c;
  
        // process matrix storage
        switch (x.storage()) {
          case 'sparse':
            switch (y.storage()) {
              case 'sparse':
                // sparse + sparse
                c = algorithm06(x, y, lcm);
                break;
              default:
                // sparse + dense
                c = algorithm02(y, x, lcm, true);
                break;
            }
            break;
          default:
            switch (y.storage()) {
              case 'sparse':
                // dense + sparse
                c = algorithm02(x, y, lcm, false);
                break;
              default:
                // dense + dense
                c = algorithm13(x, y, lcm);
                break;
            }
            break;
        }
        return c;
      },
  
      'Array, Array': function (x, y) {
        // use matrix implementation
        return lcm(matrix(x), matrix(y)).valueOf();
      },
  
      'Array, Matrix': function (x, y) {
        // use matrix implementation
        return lcm(matrix(x), y);
      },
  
      'Matrix, Array': function (x, y) {
        // use matrix implementation
        return lcm(x, matrix(y));
      },
  
      'Matrix, number | BigNumber': function (x, y) {
        // result
        var c;
        // check storage format
        switch (x.storage()) {
          case 'sparse':
            c = algorithm11(x, y, lcm, false);
            break;
          default:
            c = algorithm14(x, y, lcm, false);
            break;
        }
        return c;
      },
  
      'number | BigNumber, Matrix': function (x, y) {
        // result
        var c;
        // check storage format
        switch (y.storage()) {
          case 'sparse':
            c = algorithm11(y, x, lcm, true);
            break;
          default:
            c = algorithm14(y, x, lcm, true);
            break;
        }
        return c;
      },
  
      'Array, number | BigNumber': function (x, y) {
        // use matrix implementation
        return algorithm14(matrix(x), y, lcm, false).valueOf();
      },
  
      'number | BigNumber, Array': function (x, y) {
        // use matrix implementation
        return algorithm14(matrix(y), x, lcm, true).valueOf();
      },
  
      // TODO: need a smarter notation here
      'Array | Matrix | number | BigNumber, Array | Matrix | number | BigNumber, ...Array | Matrix | number | BigNumber': function (a, b, args) {
        var res = lcm(a, b);
        for (var i = 0; i < args.length; i++) {
          res = lcm(res, args[i]);
        }
        return res;
      }
    });
  
    lcm.toTex = '\\mathrm{${name}}\\left(${args}\\right)';
  
    return lcm;
  
    /**
     * Calculate lcm for two BigNumbers
     * @param {BigNumber} a
     * @param {BigNumber} b
     * @returns {BigNumber} Returns the least common multiple of a and b
     * @private
     */
    function _lcmBigNumber(a, b) {
      if (!a.isInt() || !b.isInt()) {
        throw new Error('Parameters in function lcm must be integer numbers');
      }
  
      if (a.isZero() || b.isZero()) {
        return new type.BigNumber(0);
      }
  
      // http://en.wikipedia.org/wiki/Euclidean_algorithm
      // evaluate lcm here inline to reduce overhead
      var prod = a.times(b);
      while (!b.isZero()) {
        var t = b;
        b = a.mod(t);
        a = t;
      }
      return prod.div(a).abs();
    }
  }
  
  /**
   * Calculate lcm for two numbers
   * @param {number} a
   * @param {number} b
   * @returns {number} Returns the least common multiple of a and b
   * @private
   */
  function _lcm (a, b) {
    if (!isInteger(a) || !isInteger(b)) {
      throw new Error('Parameters in function lcm must be integer numbers');
    }
  
    if (a == 0 || b == 0) {
      return 0;
    }
  
    // http://en.wikipedia.org/wiki/Euclidean_algorithm
    // evaluate lcm here inline to reduce overhead
    var t;
    var prod = a * b;
    while (b != 0) {
      t = b;
      b = a % t;
      a = t;
    }
    return Math.abs(prod / a);
  }
  
  exports.name = 'lcm';
  exports.factory = factory;
  