Write c program to check the password?

Answer 1

1. #include
2. #include
3. #include
4. #include
5. #define FIELD_SIZE 25
6. #define length(array) ( sizeof (array) / sizeof (array)[i] )
7. struct account {
8. char *id;
9. char *password;
10. };
11. static struct account accounts[] = {
12. { "11user1", "Pwd1" },
13. { "12user2", "Pwd2" },
14. { "13user3", "Pwd3" }
15. };
16. int is_authorized ( const char *uid, const char *pwd )
17. {
18. int i;
19. for ( i = 0; i < length ( accounts ); i++ ) {
20. if ( stricmp ( uid, accounts[i].id ) == 0 &&
21. strcmp ( pwd, accounts[i].password ) ==0 )
22. {
23. return 1;
24. }
25. }
26. return 0;
27. }
28. void get_password ( char *pwd, int size )
29. {
30. int i = 0;
31. int ch;
32. while ( i < size - 1 && ( ch = getch() ) != '\r' ) {
33. if ( ch == '\b' ) {
34. /* Don't run off the front end of the array */
35. if ( i != 0 ) {
36. printf ( "\b%c\b", ' ' );
37. --i;
38. }
39. }
40. else {
41. putchar ( '*' );
42. pwd[i++] = (char)ch;
43. }
44. }
45. pwd[i] = '\0';
46. }
47. int main ( void )
48. {
49. char uid[FIELD_SIZE];
50. char pwd[FIELD_SIZE];
51. printf ( "User ID: " );
52. fflush ( stdout );
53. if ( fgets ( uid, sizeof uid, stdin ) != NULL ) {
54. char *newline = strchr ( uid, '\n' );
55. /* Trim the newline if it's present */
56. if ( newline != NULL )
57. *newline = '\0';
58. printf ( "Password: " );
59. fflush ( stdout );
60. get_password ( pwd, sizeof pwd );
61. if ( is_authorized ( uid, pwd ) )
62. printf("\n\n\t\tUSER AUTHENTICATED\n");
63. else
64. printf("\n\n\t\tINVALID USER\n");
65. }
66. return 0;
67. }

Answer 2

string userName;

string password;

...

cout << "Username: ";

cin >> userName;

...

cout << "Password: ";

cin >> password;

...

Answer 3

You can use getch() to read the input (but not displayed) and you can print out a "*" everytime you read a char.

eg:

void readPassword(char *arr) { int i=0;char c=0;

while((c=getch()) != 'r'){

arr[i]=c; putch('*'); /* Any character you like! */

i++;

} arr[i]='';

return; }

Thus you can read password, and display ******** instead.

Answer 4

#include <iostream>

#include <string>

#include <conio.h>

using namespace std;

int main(){

string password ="";

char ch;

cout << "Enter password::\n";

ch = _getch();

while(ch != 13){//character 13 is enter

password.push_back(ch);

cout << '*';

ch = _getch();

}

if(password == "Emmanuel"){

cout << "\nAccess granted :P\n";

}else{

cout << "\nAccess aborted...\n";

}

}

Answer 5

#include
#include
#include
#define MAX 500
main()
{
char password[MAX];
char p;
int i=0;

printf("Enter the password:");

while((p=getch())!= 13){
password[i++] = p;
printf("*");
}

password[i] = '\0';

if(i<6)
printf("\nWeak password");
else
printf("\nStrong password");

printf("\nYou have entered: %s",password);

getche();
}

Answer 6

The pseudo code is as follows:

char input [80] ;

puts ("Enter password") ;

gets (input) ;

if (strcmp (input, "secret") == 0)

{

puts ("Match!") ;

}

else

{

puts ("Wrong password") ;

}

Answer 7

Just use the random function.