#include <iostream>
#include <cstdlib>
#include <cstring>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <unistd.h>
using namespace std;
int main(int argc , char **argv) {
        if (argc<2 || argc >3) {
               cout << "Usage:./as2 N [delete]" << endl;
               return 1;
        }
        int n=atoi(argv[1]);
        bool deleteShm=false;
        if (argc==3 && strcmp(argv[2],"delete")==0) {
                deleteShm=true;
        }
        int shmId=shmget(SHM_KEY,0,0666);
        if (shmId<0) {
                cout << "memory does not exist!" <<endl;
                return 1;
        }
        cout << "Memory found with shmid=" << shmId << endl;
        int *matrix=(int *) shmat(shmId,NULL,0);
        //row major
        for (int row=0;row<n;row++) {
                 for (int col=0;col<n;col++) {
                         cout << matrix[row*n+col] << " ";
                 }
                 cout << endl;
        }
        if (deleteShm) {
               shmctl(shmId,IPC_RMID,NULL);
               cout << "Memory deleted !" << endl;
        }
        return 0;

}