Teprv se ucim je to primitivni:

int yester=100, today=200, temp;
printf("yester: %d ,today: %d\n",yester,today);
printf("Swaping...\n");
temp=yester;
yester=today;
today=temp;
printf("yester: %d ,today: %d\n",yester,today);

chybu to haze na kazdem radku kde je zavorka