Otvety 3.1 mess reverse

#include <stdio.h>


int main()
{
    printf("\033[1;31m");   // set colour to red
    printf("Hello world\n");
    printf("\033[0m"); // set colour to white
    int i,j,n, m,k=1 ;
    n = 5; m = 4;

    int arr[m][n];
    for(i=0;i<m;i++)//fill an array
    {
        for(j=0;j<n;j++)
        {
            arr[i][j] = k++;
        }
    }

    printf("ARRAY BEFORE SORTING:\n");
    for(i=0;i<m;i++)//print an array
    {
        for(j=0;j<n;j++)
        {
            printf("%d\t",arr[i][j]);
        }
        printf("\n");
    }
    printf("ARRAY PRINTED IN REVERSE\n");
    for(i=m;i>=0;i--)//print an array
    {
        for(j=n;j>=0;j--)
        {
            printf("%d\t",arr[i][j]);
        }
        printf("\n");
    }
    for(i=m;i>=0;i--)//move elements forward
    {printf("%d %d\t",i,j);
        for(j=n;j>=0;j--)
        {
            //if((i!=m)&&(j!=n))//all rows exepts last, all columns exept last
            if(i!=0)
            {
               arr[i][j]= arr[i][j-1];
            }
            else //fill last element in each row
            {
                arr[i][j] = arr[i-1][n];
            }

        }
    }
    printf("\nARRAY AFTER SORTING:\n");
    for(i=0;i<m;i++)//print an array
    {
        for(j=0;j<n;j++)
        {
            printf("%d\t",arr[i][j]);
        }
        printf("\n");
    }


    return 0;
}