Thread: Generating a 4-digit number with distinct digits?

I've started programming a "Bulls and Cows" game.I got through the two player mode(which is easy). Now for the single player, I know how to generate a random number but I have a problem in generating a number with distinct digits(4-digit number)?Can anyone help me out?

Example:The number can be 1234 not 1133 or 2448.

[code]
#include <stdlib.h>
#include <iostream.h>
#include <conio.h>

void main()
{
char guess[10], word[10];
int turns, a, b, bulls, cows;
clrscr();
cout<<"Welcome to Bulls & Cows \n\nPlayer 1, enter the letters(distinct) of your word: ";
cin.getline(word,sizeof(word));
clrscr();
cout<<"\nPlayer2, please get ready.";

for(turns=1;turns<=10;turns++)
{
bulls=0;cows=0;
cout<<"\nEnter Guess : "<<turns;
cin.getline(guess,sizeof(guess));

for(a=0;a<4;a++)
{
if(guess[a]==word[a])
{
bulls++;
}
else
{
for(b=0;b<4;b++)
{
if(guess[a]==word[b])
{
cows++;
}
}
}
}

if(bulls==4)
{
cout<<"\nYou are Victorious!\n";
break;
}else
{
cout<<"\nBulls ="<<bulls<< "Cows ="<<cows;
}
}

getch();
}
[\code]

data structures - An Efficient way of randomizing an array - Shuffle code - Stack Overflow
Put digits 1 to 9 in an array
shuffle
take the first 4

Another approach is to generate a random four digit number, check if any digits are repeated, and if so throw the number away and generate another one.

Sounds dumb, but is in fact a common way of generating samples of a specific distribution.

Use code tags, don't use void main, use std::string, and don't use getch (non-standard).

Originally Posted by droidbreath

I'm new to c++ and this is how they teach in our school.

This is an opportunity for you to learn yourself better C++ than the (seemingly) junk your school teaches you. It will also be of more use to you in real life.