simple password program problem in c++

Replies

• 

  Manish Goyal

  try this code if you find difficulty in understanding this code
  then post it here
  
  

  #include
  #include
  int check(char a[],char b[]);
  void main()
  {
  clrscr();
  char pwd[5],def[]="sumit";
  int i=0,mycheck;
  cout<<"Please enter password:-";
  while(i<5)
  {
  pwd[i]=getch();
  cout<<"*";
  ++i;
  }
  cout<
                                      

• 

  gaurav.bhorkar

  sumit_goel

  hello friends
  i m beginners of c++ and i want to make simple password program that will accept password from user and simultaneously display the stars("*") with the simple while loop.
  i have written the code of this program but this is showing wrong result.Pls help me in solving this problem.
  The Code :

  Your code:
  

  #include
  #include
  void main()
  {
  clrscr();
  char pwd[5]; [COLOR=Blue]// This should be of length 6, "sumit" measures 5 but one extra for '\0'[/COLOR]
  int i=0;
  while(i<5)
  {
  pwd[i]=getch(); [COLOR=Blue]/* There is no equivalent for getch() in std C++. you have to compile this as a C program */[/COLOR]
  cout<<"*";
  ++i;
  }
  cout<Here is my C equivalent. I used C because I wanted to use getch () which we cannot use in C++. Moreover, there is no equivalent function to getch () in C++.
  
  What getch () does is, taking a single keystroke as input. I tried using cin.get () in C++ which is equivalent to getchar() in C which takes a keystroke but waits for the Enter key.
  
  
  
  So, here is the C code,
  
  #include
  #include 
  #include 
  #include 
  int main()
  {
  system ("cls"); /[COLOR=Blue]/ clrscr () equivalent[/COLOR]
  char pwd[6]; [COLOR=Blue]// as i said, length should be 6 to accommodate the null character.[/COLOR]
  int i=0;
  while(i<5) [COLOR=Blue]//because the string is of length 5[/COLOR]
  {
  pwd[i]= getch ();
  printf ("*");
  ++i;
  }
  pwd[5] = '\0';[COLOR=Blue] // Null character which signifies the end of string.[/COLOR]
  printf ("\n");
  if (!strcmp (pwd, "sumit")) [COLOR=Blue]/* strcmp returns 0 if the strings are identical, hence the ! 
  operator, ie. the NOT logical operator. (so 0 becomes 1 i.e. True) */[/COLOR]
  printf ("correct password\n");
  else
  printf ("wrong password\n");
  
  system ("pause");[COLOR=Blue] // getch ()[/COLOR]
  }
  I hope you get it.
                                      

• 

  gaurav.bhorkar

  @goyal420, which compiler did you use? Your program isn't compiling in VC++.
• 

  Manish Goyal

  I used C because I wanted to use getch () which we cannot use in C++.

  I don't agree with this statement .YES we can use this function
  
  It is available in conio.h file
  
  

  @goyal420, which compiler did you use? Your program isn't compiling in VC++.

  Borland C++ Compiler 5.5
  
  Is it really necessary to take extra memory for null character also ????
  I mean can't you take char pwd[5]; only
• 

  Morningdot Hablu

  hello guy's
  up to what i know getch() is not an c or c++ function.
  it is a compiler extension. you can use it in either c or c++ if your compiler support it.
  @ goyal
  @gaurav
  here the header taken by you guy's are not standard(ANSI standered).
  is standard, is not
  
  >getch() is still available int the conio.h header file (at least in MinGW).
  I'm sure it works just fine on your compiler, but because it's non-standard, that means it's not guaranteed to work on my compiler, or someone else's compiler.
• 

  gaurav.bhorkar

  goyal420

  Is it really necessary to take extra memory for null character also ????
  I mean can't you take char pwd[5]; only

  Going by your program, taking pwd[5] works perfectly, because you have checked each and every character in check() function.
  But according to the definition of a string, the last character is the '\0' null character. It is required because the compiler (or std lib functions) should know where the string ends.
  
  Regarding the conio.h file, it is a non standard file written by Borland for use in Turbo C compilers. The modern compilers like GCC and VC++ doesn't support it. Try it, VC++ says, "cannot find conio.h".
• 

  gaurav.bhorkar

  mohit007kumar00

  hello guy's
  up to what i know getch() is not an c or c++ function.
  it is a compiler extension. you can use it in either c or c++ if your compiler support it.
  @ goyal
  @gaurav
  here the header taken by you guy's are not standard(ANSI standered).
  is standard, is not
  
  >getch() is still available int the conio.h header file (at least in MinGW).
  I'm sure it works just fine on your compiler, but because it's non-standard, that means it's not guaranteed to work on my compiler, or someone else's compiler.

  According to standard C++, is not correct (but works), it should be .
  
  I've used C, so in C you have to write . The extension .h is necessary.
  
  @goyal420: You program will definitely work in Turbo C/C++ compilers. No offense meant, your program is written in C++, but with a C accent. According to modern standards, main () in C++ should always return an int. You haven't used the namespace std. Thats why it is not working in VC++.
• 

  ankesh.cs2007

  i agree with gaurav bhorkar
• 

  vignesh kumar selvakumar

  #-Link-Snipped-# the password program is not working , in pwd some junk value is getting stored , pls help.
• 

  Vishal Sharma

  sumit_goel

  hello friends
  i m beginners of c++ and i want to make simple password program that will accept password from user and simultaneously display the stars("*") with the simple while loop.
  i have written the code of this program but this is showing wrong result.Pls help me in solving this problem.
  The Code :
  

  #include
  #include
  void main()
  {
  clrscr();
  char pwd[5];
  int i=0;
  while(i<5)
  {
  pwd[i]=getch();
  cout<<"*";
  ++i;
  }
  cout<

  I wrote this code, kinda long back when I was new at CE. It's simple and written in C, shouldn't be much problem for you to convert that in C++. After all, there's some work even you should do instead of a simple copy paste 😀
  
  

  #include
  #include
  int main() {
      char pwd[50],c;
      int i = 0, done=0;
      while(!done) {
          c = getch();
          switch(c) {
              case '\r':
                  pwd[i] = '\0';
                  done = 1;
                  break;
              case '\b':
                  i--;
                  fputs("\b \b",stdout);
                  break;
              default:
                  pwd[i++] = c;
                  putchar('*');
          }
      }
      putchar('\n');
      fputs(pwd,stdout);
  }
  

• 

  Vishal Sharma

  oh, my bad! didn't notice how old this post is
• 

  mohit gahlot

  #include
  #include
  #include
  using namespace std;
  
  int main()
  {
  string password;
  char ch[10];
  int k=0;
  cout<<"Enter password\n";
  ch[k]=_getch();
  while(ch[k]!=13)
  {
  if(ch[k]!=8)
  {
  cout<<"*";
  k++;
  }
  else
  {
  k--;
  cout<<"\b \b";
  }
  
  ch[k]=_getch();
  }
  for(int i=0;i {
  password.push_back(ch);
  }
  }
  // Try this, it is simple and easy
• 

  rambaburai911

  #include
  #include
  #include
  void main()
  {
  clrscr();
  char *a,*b="ramramram";
  int I,r=0;
  ram :
  cout<<"enter your password:";
  for(I=0;l<9;l++)
  {
  a=getch();
  cout<<"*";
  }
  r=strcmp(a,b);
  if(r==0)
  cout<<"correct password";
  else
  {cout<<"incorrect password:";
  goto ram;}
  getch();
  }
• 

  rambaburai911

  Hii I am a student of class12 science
  

  rambaburai911

  #include
  #include
  #include
  void main()
  {
  clrscr();
  char *a,*b="ramramram";
  int I,r=0;
  ram :
  cout<<"enter your password:";
  for(I=0;l<9;l++)
  {
  a=getch();
  cout<<"*";
  }
  r=strcmp(a,b);
  if(r==0)
  cout<<"correct password";
  else
  {cout<<"incorrect password:";
  goto ram;}
  getch();
  }[/QUOTEI]