尝试验证文本文件中的字符时陷入循环

Question

我必须编写一个程序，从文本文件中读取一些 "random" 字母和数字字符串，并检查它们是否满足使它们成为有效密码的某些条件。

条件是：-刚好有4位数字 -正好有8个字符 -至少有一个大写字母和至少一个小写字母

程序读取文件并输出有效密码的数量。

这是文本文件的格式： "eR68G12a 91jY643ebjp eRty74kLh 24fG92 aj85gt32 dGb9357jKoup2 "（单行）

代码： ´´´

Program Ej23_version3;

var 
char1,char2:char;
mayus,minus:boolean; // mayus and minus would be uppercase and lowercase respectively
cantDigitos,cantCaracteres,contrasenasValidas:integer;
datos:text;

Begin 
assign(datos,'Datos_guia3_ej23.txt'); reset(datos);
contrasenasValidas := 0;

char1 := ' ';

Read(datos,char2);
while not eof(datos) do 
Begin 
    mayus := false; minus := false; cantDigitos := 0; cantCaracteres := 0;
    if (char1 = ' ') and (char2 <> ' ') then //check if its the beggining of the word
    Begin 
        while not eof(datos) and (char2 <> ' ') do 
        Begin 
            cantCaracteres := cantCaracteres + 1;
            if char2 = UPCASE(char2) then  // if the character2 is equal to the uppercase version of the character2, character2 is uppercase
                mayus := true
            else
                if (char2 in ['0'..'9']) then
                cantDigitos := cantDigitos + 1
                else
                    minus := true;
        if eof(datos) then // when it reaches the end of the file, it also reads and checks the last character
            if char2 = UPCASE(char2) then 
                mayus := true
            else
                if (char2 in ['0'..'9']) then
                cantDigitos := cantDigitos + 1
                else
                    minus := true;
        End;

        if minus and mayus and (cantDigitos = 4) and (cantCaracteres = 8) then //if all conditions are met, the password is valid and its added to the counter
            contrasenasValidas := contrasenasValidas + 1;

        char1 := char2; Read(datos, char2); //char2 should be an empty character by this point, so it passes that value to char1 and reads the next character
    End
End;

WriteLn(contrasenasValidas);
End.

但是当我运行它时，它只是卡在那里，只有提示滴答作响

Answer 1

问题在于您读取文件的方式（逐个字符）。

最好一下子看完，把八个字的字串一个一个看完

uses
  SysUtils;

var
  LFile: TextFile;
  LStr, LSubStr: string;
  LStartIndex: integer;
  LExit: boolean;

begin
  AssignFile(LFile, 'Datos_guia3_ej23.txt');
  Reset(LFile);
  ReadLn(LFile, LStr); // Get the whole line

  LStartIndex := 1; // Search all 8 characters sequences, starting from the first character
  LExit := FALSE;
  repeat
    LSubStr := Copy(LStr, LStartIndex, 8);
    if Length(LSubStr) = 8 then
    begin
      // Here check other conditions
      // ...

      Inc(LStartIndex);
    end else
      LExit := TRUE;
  until LExit;

  CloseFile(LFile);
end.

尝试验证文本文件中的字符时陷入循环

Stuck on a loop while trying to verify characters from a text file

pascal

freepascal