How can i write an array starting from right to left in C-CodePudding

I don't want to reverse or shift the array. What I want is to write the array from right to left.

I did something like

int arr[5] = {0};
for (int i = 0; i < 5; i  )
{
    cout << "enter a number : ";
    cin >> arr[i];
    for (int j = 0; j < 5; j  )
    {
        if (arr[j] != 0)
        {
            cout << arr[j] << " ";
        }
        else
            cout << "X ";
    }
    
    cout << endl;
    
}

and on the output screen I see this

enter a number : 5
5 X X X X
enter a number : 4
5 4 X X X
enter a number : 3
5 4 3 X X
enter a number : 2
5 4 3 2 X
enter a number : 1
5 4 3 2 1
Press any key to continue . . .

but i want to see this

enter a number : 5
X X X X 5
enter a number : 4
X X X 5 4
enter a number : 3
X X 5 4 3
enter a number : 2
X 5 4 3 2
enter a number : 1
5 4 3 2 1
Press any key to continue . . .

how can I do that?

I will be glad if you help.

CodePudding user response：

Just change the inner for loop for example the following way

int j = 5;

for ( ; j != 0 && arr[j-1] == 0; --j )
{
    std::cout << 'X' << ' ';
}

for ( int k = 0; k != j; k   )
{
    std::cout << arr[k] << ' ';
}

CodePudding user response：

I think you are trying to write into the last index each time, and then move each number backwards in the array?

To write into the last index use cin >> arr[4]. Then After printing out the array copy each value into the previous index. Make sure that your copy only when the J index is less than 4

int arr[5] = {0};
for (int i = 0; i < 5; i  )
{
    cout << "enter a number : ";
    //write into the last position
    cin >> arr[4];

    for (int j = 0; j < 5; j  )
    {
        if (arr[j] != 0)
        {
            cout << arr[j] << " ";
        }
        else
            cout << "X ";
        
        //don't go out of bounds. This should move each number to the previous index
        if(j<4){
            arr[j]=arr[j 1];
        }
    }
    
    cout << endl;
    
}