#include<stdio.h>

#define PP_INC_0 1
#define PP_INC_1 2
#define PP_INC_2 3
#define PP_INC_3 3

#define PP_INC(n) PP_INC_I(n)
#define PP_INC_I(n) PP_INC_ ## n

#define PP_DEC_0 0
#define PP_DEC_1 0
#define PP_DEC_2 1
#define PP_DEC_3 2

#define PP_DEC(n) PP_DEC_I(n)
#define PP_DEC_I(n) PP_DEC_ ## n

#define PP_IF_0(t, f) f
#define PP_IF_1(t, f) t

#define PP_IF(c, t, f) PP_IF_I(c, t, f)
#define PP_IF_I(c, t, f) PP_IF_ ## c (t, f)

#define PP_BOOL_0 0
#define PP_BOOL_1 1
#define PP_BOOL_2 1
#define PP_BOOL_3 1

#define PP_BOOL(n) PP_BOOL_I(n)
#define PP_BOOL_I(n) PP_BOOL_ ## n

#define PP_TUPLE_ELEM_1_0(a) a
#define PP_TUPLE_ELEM_2_0(a, b) a
#define PP_TUPLE_ELEM_2_1(a, b) b
#define PP_TUPLE_ELEM_3_0(a, b, c) a
#define PP_TUPLE_ELEM_3_1(a, b, c) b
#define PP_TUPLE_ELEM_3_2(a, b, c) c

#define PP_TUPLE_ELEM(n, i, tup) PP_TUPLE_ELEM_I(n, i, tup)
#define PP_TUPLE_ELEM_I(n, i, tup) PP_TUPLE_ELEM_ ## n ## _ ## i tup

#define PP_ADD(m, n) PP_TUPLE_ELEM(2, 1, PP_ADD_I(PP_ADD_I(PP_ADD_I(PP_ADD_I(PP_ADD_I(PP_ADD_I(PP_ADD_I(PP_ADD_I((m, n))))))))))
#define PP_ADD_I(tup) PP_ADD_II tup
#define PP_ADD_II(m, n) PP_IF(PP_BOOL(m), (PP_DEC(m), PP_INC(n)), (m, n))

#define PP_TO_STR(a) PP_TO_STR_I(a)
#define PP_TO_STR_I(a) PP_TO_STR_II(a)
#define PP_TO_STR_II(a) #a

main() {
  printf("%s", PP_TO_STR(PP_ADD(1, 2)));
  return 0;
}

3