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/**
 *  Function to validate CNPJ in javascript
 * @param cnpj
 * @returns {boolean}
 */
function validarCNPJ(cnpj) {
    var cnpj = cnpj.replace(/[^\d]+/g,'');

    if(cnpj == '') return false;

    if (cnpj.length != 14)
        return false;

    if (cnpj == "00000000000000" ||
        cnpj == "11111111111111" ||
        cnpj == "22222222222222" ||
        cnpj == "33333333333333" ||
        cnpj == "44444444444444" ||
        cnpj == "55555555555555" ||
        cnpj == "66666666666666" ||
        cnpj == "77777777777777" ||
        cnpj == "88888888888888" ||
        cnpj == "99999999999999")
        return false;

    var size = cnpj.length - 2
    var numbers = cnpj.substring(0,size);
    var digits = cnpj.substring(size);
    var sum = 0;
    var pos = size - 7;
    for (var i = size; i >= 1; i--) {
        sum += numbers.charAt(size - i) * pos--;
        if (pos < 2)
            pos = 9;
    }
    var result = sum % 11 < 2 ? 0 : 11 - sum % 11;
    if (result != digits.charAt(0))
        return false;

    size = size + 1;
    numbers = cnpj.substring(0,size);
    sum = 0;
    pos = size - 7;
    for (i = size; i >= 1; i--) {
        sum += numbers.charAt(size - i) * pos--;
        if (pos < 2)
            pos = 9;
    }
    result = sum % 11 < 2 ? 0 : 11 - sum % 11;
    if (result != digits.charAt(1))
        return false;

    return true;
}