Function Template
enables us to define a function that works for multiple data types.
template <typename T>
int compare(T a,T b) {
if(a < b) return -1;
else if(a > b) return 1;
else return 0;
}
int main() {
int x = 2;
int y = 3;
printf("%d\n",compare(x,y));
double a = 2.3;
double b = 1.3;
printf("%d\n",compare(a,b));
}