#include <stdio.h>

int main(void) {

  int a = 0, b = 0, 
      c = 2, d = 2;

  a += 2; b += 3;
  c -= 4; d -= 5;

  printf("a: %d, b: %d, c: %d, d: %d\n", a,b,c,d);
  
  return 0;
}