C++ For-Loop Gets stuck when entering new variables [closed] - c++

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I'm new to C++ and trying to create a lottery game for a college project.
I have a for loop to check that there are no duplicate numbers in the array entered. This works absolutely fine when you take out the section of code to produce the random numbers.
As soon as I add the random number section back in, the for loop just gets stuck. It will continuously tell me that i have already entered the number when its trying to store the first number.
I have attached all of my code, apologies if you don't need it all.
#include <iostream>
#include <stdio.h>
#include <time.h>
#include <stdlib.h>
using namespace std;
//int loto[6];
int main()
{
int numbers[6];
//void rand_num(int loto[6], int count);
int loto[6]; //used to store the loto numbers
//int james = 0;
//int l,j; //used in checking any duplicated
srand(time(0));
for(int count=0; count<6; count++)
{
loto[count] = (rand()%49)+1;
cout << loto[count] << endl;
}
//declares the variable i to increase each time a number is entered.
//this will only go as high as 6
for(int i=0;i<6;i++)
{
cout<<" " << i<<" : Please enter your lottery numbers: "<<endl;
cin>>numbers[i];
if ((numbers[i] >= 50) | (numbers[i] == 0))
do
{
{
//checks to see if the first number entered is above 50 or = to 0 and rejects it
cout << "The Number must be between 1-49, please select again. " << endl;
cin >> numbers[i];
}
}
while ((numbers[i] >= 50) | (numbers[i] == 0));
//----------------------------------------------------------------------------
//this section of code is a loop within a loop to check the number entered against all numbers already stored.
//makes l the same as i effectively
for(int l=0;l<6;l++)
{
//makes j one more than l
for(int j=l+1;j<7;j++)
{
if( numbers[l] == numbers[j] )
do
{
{
cout << "Number has already been chosen, please re-enter number " << endl;
cout << endl;
cin >>numbers[i];
//checks the number that is re-entered is not <50 or = 0
//if so it rejects it and asks for another as above.
if ((numbers[i] >= 50) | (numbers[i] == 0))
do
{
{
cout << "The Number must be between 1-49, please select again. " << endl;
cin >> numbers[i];
}
}
while ((numbers[i] >= 50) | (numbers[i] == 0));
}
}
while (numbers[l] == numbers[j]);
}
}
}
//----------------------------------------------------------------------------
//this displays the numbers that have been chosen.
cout << "Your Numbers are: " << endl;
for (int i = 0; i<6; i++)
{
cout << " " << numbers[i];
}
return 0;
}

Answer 1

I'm not sure this is the real problem but it is a bug. Try to correct it and see if it helps.
for(int l=0;l<6;l++)
{
//makes j one more than l
for(int j=l+1;j<7;j++)
{
if( numbers[l] == numbers[j] )
The inner-loop will reach j==6 so you will access outside the array. The outer-loop shall have 5 as the limit and the inner-loop shall have 6 as the limit.
EDIT:
After looking a bit more at your code I can see that you are using numbers[] without initializing it. The two nested for-loops will compare all elements in numbers. But if the user have only entered 2 numbers, the rest is unitialized and can give unintended results.
Further - you don't need to check all elements againt all elements every time. Just check the newly entered number (index by i) with all previous numbers.
Finally you will probably need something like:
if (!(cin >> numbers[i])) {
cout << "Please enter numbers only." << endl;
cin.clear();
cin.ignore(10000,'\n');
}
to handle input not being integer, e.g. "text"
And to minor things:
You should also check for negative numbers.
You are using | instead of ||. It will work fine but || seems more correct as it is the logical OR (while | is a binary OR).