Multiple stacks in 1 Dimensional Array

Multiple stacks in 1 Dimensional Array

#include<stdio.h>
#include<stdlib.h>
#define MAX 12

int stack[MAX];
int m=MAX, n;
int top[10], boundary[10];

void push(int i, int item )
{
          if(top[i] == boundary[i+1])
          {
                    printf("\nStack%d overflow", i);
          }
          else
         {
                   top[i] = top[i] +1;
                   stack[top[i]] = item;
         }
}
void pop(int i)
{
         int item;
         if(top[i] == boundary[i])
         {
                  printf("\nStack%d underflow", i);
         }
         else
        {
                 item = stack[top[i]];
                 printf("\nItem that got deleted from stack%d is %d", i, item);
                 top[i] = top[i] - 1;
         }
}

void display(int i)
{
          int j;
          if(top[i] == boundary[i])
          {
                     printf("\nStack%d is empty", i);
                     return;
          }
          else
         {
                    printf("\n");
                    for(j=top[i]; j>=boundary[i]+1; j--)
                               printf("| %d |\n",stack[j]);
          }
}

void main()
{
          int ch, stackno, item,i;
          printf("\nEnter the number of stacks: ");
          scanf("%d",&n);
          for(i=0;i<n;i++)
          {
                  top[i] = boundary[i] = (i*(m/n)) - 1;
                  printf("\ntop[%d] = %d and boundary[%d] = %d",i,top[i], i, boundary[i]);
          }
          boundary[i] = MAX-1;
   
          while(1)
          {
                  printf("\n\n~~~MENU~~~");
                  printf("\n1.Push operation");
                  printf("\n2.Pop operation");
                  printf("\n3.Display");
                  printf("\n4.Exit");
                  printf("\nPlease enter your choice: ");
                  scanf("%d", &ch);
                  switch(ch)
                 {
                            case 1: printf("\nEnter a item to be pushed: ");
                                        scanf("%d",&item);
                                        printf("\nEnter the stack number: ");
                                        scanf("%d",&stackno);
                                        push(stackno, item);
                                        break;

                           case 2: printf("\nEnter the stack number: ");
                                       scanf("%d",&stackno);
                                       pop(stackno);
                                       break;

                          case 3: for(stackno=0;stackno<n;stackno++)
                                     {
                                              printf("\nStack%d contents are: ", stackno);
                                              display(stackno);
                                     }
                                     break;

                          case 4:exit(0);
                          default: printf("\nPlease enter a valid choice");
                                       break;
                }
       }
}

Output:

Enter the number of stacks: 3

top[0] = -1 and boundary[0] = -1
top[1] = 3  and boundary[1] = 3
top[2] = 7  and boundary[2] = 7

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 1
Enter a item to be pushed: 11
Enter the stack number: 0

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 1
Enter a item to be pushed: 12
Enter the stack number: 0

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 1
Enter a item to be pushed: 13
Enter the stack number: 0

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 1
Enter a item to be pushed: 14
Enter the stack number: 0

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 1
Enter a item to be pushed: 15
Enter the stack number: 0
Stack0 overflow

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 1
Enter a item to be pushed: 21
Enter the stack number: 1

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 1
Enter a item to be pushed: 22
Enter the stack number: 1


~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 1
Enter a item to be pushed: 23
Enter the stack number: 1

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 1
Enter a item to be pushed: 31
Enter the stack number: 2

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 1
Enter a item to be pushed: 32
Enter the stack number: 2

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 1
Enter a item to be pushed: 33
Enter the stack number: 2

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 3
Stack0 contents are:
| 14 |
| 13 |
| 12 |
| 11 |

Stack1 contents are:
| 23 |
| 22 |
| 21 |

Stack2 contents are:
| 33 |
| 32 |
| 31 |


~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 2
Enter the stack number: 1
Item that got deleted from stack1 is 23

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 3

Stack0 contents are:
| 14 |
| 13 |
| 12 |
| 11 |

Stack1 contents are:
| 22 |
| 21 |

Stack2 contents are:
| 33 |
| 32 |
| 31 |

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 2
Enter the stack number: 1
Item that got deleted from stack1 is 22

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 2
Enter the stack number: 1
Item that got deleted from stack1 is 21

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 2
Enter the stack number: 1
Stack1 underflow

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 3

Stack0 contents are:
| 14 |
| 13 |
| 12 |
| 11 |

Stack1 contents are:
Stack1 is empty

Stack2 contents are:
| 33 |
| 32 |
| 31 |

~~~MENU~~~
1.Push operation
2.Pop operation
3.Display
4.Exit
Please enter your choice: 4