/* Stack Operations */

#define PUSH 0
#define POP 1

/* Arithmetic instructions */

#define ADD 2
#define SUB 3
#define MUL 4

/* Memory instructions */

#define LD 5
#define ST 6

/*Control instructions */

#define JMP 7
#define JEQ 8
#define CMP 9

/* Empty operand */

#define EMPTY 98

/* End instruction */

#define END 99

/* Machine configuration */

#define MEM_SIZE 4
#define STACK_SIZE 30

/* Instruction type */

struct inst
{
  int opcode;
  int val;
};