[saltycracker]

Write a function that will produce the numbers 1 - 10 randomly and not return the same value twice.

Example:

Say I call my function getNum

The first time I call getNum it may produce:
7

The second time I call getNum it may produce:
3

The third time I call getNum it nay produce:
10

The fourth time I call getNum it may produce:
8

The fifth time I call getNum it may produce:
2

The sixth time I call getNum it nay produce:
1

The seventh time I call getNum it nay produce:
4

The eigtht time I call getNum it may produce:
5

The nineth time I call getNum it may produce:
9

The tenth time I call getNum it nay produce:
6

Good luck... C++'ers, try to say away from container classes.

Note: What happens at the end of the cycle is up to you. You can reset the function to start again of just do nothing.

[FoxBlood]

Am I allowed to use rand() function?

[saltycracker]

Am I allowed to use rand() function?

Yes and srand too.

I just want people to think about a way to solve this without relying on a container class.

[FoxBlood]

Code

int arr[11];
int random_numer()
{
   int number = rand() % 10 + 1;
   if(arr[number] == 1)
       return random_numer();
   else
   {
       arr[number] = 1;
       return number;
   }
}

Something like this?

[HFDone]

very simple
with C you can use array for the rand values
with C++ you can use std::array

[saltycracker]

Very important... You must return the values 1 through 10 randomly and no repeats.

[FoxBlood]

Code

void random_numers()
{
    srand (time(NULL));
    int arr[11] = {0};
    for(int i = 1; i<=10;i++)
    {
        int number = rand() % 10 + 1;
        if(arr[number] == 1)
            i--;
        else
        {
            cout<<number<<" ";
            arr[number] = 1;
        }
    }
}

My best code I ever write. Isn't it?

[saltycracker]

Code

void random_numers()
{
   srand (time(NULL));
   int arr[11] = {0};
   for(int i = 1; i<=10;i++)
   {
       int number = rand() % 10 + 1;
       if(arr[number] == 1)
           i--;
       else
       {
           cout<<number<<" ";
           arr[number] = 1;
       }
   }
}

My best code I ever write. Isn't it?

Wow! I mean Wow! Why would you write it like that? For lol's?

[akali]

Code

int getNum(int* array,int index){
    int r = 0;
    do{
        r = rand() % 11 ;
        for(int i = 0; i < index;++i){
            
            if(r == array[i]){
                r = 0;
            }
        }
    }while(r == 0);
    return r;
}
int main(){
    int array[10] = {0};
    for(int i = 0; i < 10; ++i){
        array[i] = getNum(array,i);
         printf("%i\n",array[i]);
    }
}

[saltycracker]

Code

int getNum(int* array,int index){
   int r = 0;
   do{
       r = rand() % 11 ;
       for(int i = 0; i < index;++i){
           
           if(r == array[i]){
               r = 0;
           }
       }
   }while(r == 0);
   return r;
}
int main(){
   int array[10] = {0};
   for(int i = 0; i < 10; ++i){
       array[i] = getNum(array,i);
        printf("%i\n",array[i]);
   }
}

So far... You are making it way more difficult than it has to be. You don't need a loop to solve the problem.

[HFDone]

PHP Code


<?php 
int getNum(int* array,int index){
   int r = 0;
   r = rand() % 10 + 1;
   for(int i = 0; i < index; ++i){
      if(r == array[i]){
         r = getNum(array, i + 1);
      }
   }
   return r;
}

int main(){
   int array[10] = {0};
   for(int i = 0; i < 10; ++i){
       array[i] = getNum(array, i);
        printf("%i\n", array[i]);
   }
} 


[saltycracker]

PHP Code


<?php 
int getNum(int* array,int index){
   int r = 0;
   r = rand() % 10 + 1;
   for(int i = 0; i < index; ++i){
      if(r == array[i]){
         r = getNum(array, i + 1);
      }
   }
   return r;
}

int main(){
   int array[10] = {0};
   for(int i = 0; i < 10; ++i){
       array[i] = getNum(array, i);
        printf("%i\n", array[i]);
   }
} 


What is it with the loops? You don't need a loop or recursion to solve this problem.

[severos]

PHP Code


<?php 
int getNum(){
  static int[] arr = {8,5,1,9,7,6,3,4,2,10}
  static idx = 0;
  if(idx > 9)
    return 0; // already done all numbers
  return arr[idx++];
} 


Is this considered random enough?

[saltycracker]

Here's what I did..

Spoiler (Click to View)

Code

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#define ARR_SIZE 10

int getNum() {
 static size_t size = 10;
 static int arr[ARR_SIZE] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
 int pos = rand() % size;
 int ans = arr[pos];
 int temp = arr[size - 1];
 arr[size - 1] = ans;
 arr[pos] = temp;
 size--;//can reset size here when it reaches 0
 return ans;
}

int main(int argc, char ** argv) {
 srand((unsigned) time(NULL));
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 return 0;
}

[0xDEAD10CC]

Here's what I did..

Spoiler (Click to View)

Code

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#define ARR_SIZE 10

int getNum() {
 static size_t size = 10;
 static int arr[ARR_SIZE] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
 int pos = rand() % size;
 int ans = arr[pos];
 int temp = arr[size - 1];
 arr[size - 1] = ans;
 arr[pos] = temp;
 size--;//can reset size here when it reaches 0
 return ans;
}

int main(int argc, char ** argv) {
 srand((unsigned) time(NULL));
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 fprintf(stdout, "%d\n", getNum());
 return 0;
}

Why define a constant ARR_SIZE then not use it to assign your size variable? That makes it nearly useless, you could have just omitted the constant and all usages of it to get the same effect. You also have an extra variable in there that you don't need: