using static System.Console;
public class Test {
public static void Main() {
WriteLine(FormatarCpf("12345678901"));
WriteLine(FormatarCpf("00123456789"));
}
static string FormatarCpf(string cpf) {
return cpf.Substring(0, 3) + "." + cpf.Substring(3, 3) + "." + cpf.Substring(6, 3) + "-" + cpf.Substring(9, 2);
}
}
//https://pt.stackoverflow.com/q/75498/101
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