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function valid_cpf(value) {
    var Soma;
    var Resto;
    Soma = 0;
    value = value.replace('-', '');
    value = value.replace('.', '');
    value = value.replace('.', '');
    value = value.replace('.', '');
    value = value.replace(',', '');
    if (value.length !== 11) return false;
    if (value == "00000000000" || value == "11111111111" || value == "22222222222" || value == "33333333333" || value == "44444444444" || value == "55555555555" || value == "66666666666" || value == "77777777777" || value == "88888888888" || value == "99999999999") return false;
    for (i=1; i<=9; i++) Soma = Soma + parseInt(value.substring(i-1, i)) * (11 - i);
    Resto = (Soma * 10) % 11;
    if ((Resto == 10) || (Resto == 11))  Resto = 0;
    if (Resto != parseInt(value.substring(9, 10)) ) return false;
    Soma = 0;
    for (i = 1; i <= 10; i++) Soma = Soma + parseInt(value.substring(i-1, i)) * (12 - i);
    Resto = (Soma * 10) % 11;
    if ((Resto == 10) || (Resto == 11))  Resto = 0;
    if (Resto != parseInt(value.substring(10, 11) ) ) return false;
    return true;
}

if (!valida_cpf('00000000000')) {
  alert('CPF é inválido!!');
}