To declare a variable, write the type followed by a list of variables of
that type:
type_namevariable_name_1, ..., variable_name_n;
For example:
int last_year, cur_year;
long double earth_mass, mars_mass, venus_mass;
unsigned int num_pets;
long city_pop, state_pop;
state_pop = city_pop = 5000000;
short moon_landing = 1969;
float temp1, temp2, temp3;
temp1 = 98.6;
temp2 = 98.7;
temp3 = 98.5;
double bignum, smallnum;
bignum = 2.36e208;
smallnum = 3.2e-300;
Always declare your variables. A compiler will catch a missing
declaration every time and terminate compilation, complaining
bitterly. (You will often see a host of error messages, one for each use
of the undeclared variable. See Debugging.)