paging.c

#include <stdio.h>

#define PAGE_SIZE 100
#define PAGE_TABLE_SIZE 128

struct pentry
{
  int no;
  int start_addr;
} ptable[PAGE_TABLE_SIZE];

char memory[PAGE_SIZE * PAGE_TABLE_SIZE];

int get_physical_address(int logical_address)
{
  int page_no = logical_address / PAGE_SIZE;
  int offset  = logical_address % PAGE_SIZE;
  return ptable[page_no].start_addr + offset;
}

int main()
{
  int entry_flag=0, translate_flag=0, phy_addr, logical_addr;
  char data, choice;
  int n, i;
  printf("\nEnter the number of pages to allocate ");
  scanf("%d", &n);

  for(i=0;i<n;i++)
    {
      printf("\nEnter Starting Address for Page %d: ", i);
      scanf("%d", &ptable[i].start_addr);
      ptable[i].no = i;
    }

  while(entry_flag==0)
    {
      printf("\nEnter the logical address of data to be modified: ");
      scanf("%d", &logical_addr);

      printf("\nEnter the data to be set at the given location: ");
      scanf("%c", &data);
      
      phy_addr = get_physical_address(logical_addr);
      memory[phy_addr] = data;

      printf("\nData successfully stored at physical address %d. \nModify more data? (y/n) ", phy_addr);
      scanf("%c", &choice);
      if(choice=='n') entry_flag=1;
    }

  while(translate_flag==0)
    {
      printf("\nEnter the logical address to be translated: ");
      scanf("%d", &logical_addr);

      phy_addr = get_physical_address(logical_addr);
      data = memory[phy_addr];
      printf("\nLogical Address %d = Physical Address %d. Data is %d", logical_addr, phy_addr, data);

      printf("\nContinue? (y/n) ");
      scanf("%c", &choice);
      if(choice=='n') translate_flag=1;
    }
  return 0;
}

is it possible to explain the code