http://www.infosys.utas.edu.au/info/documentation/C/CStdLib.html

no wonder. i'm using gcc.

this is a pretty standard first program:
#include <iostream.h>
int main() {
cout << "Hello, World!" << endl;
return 0;
}

what is the answer? i get these errors when compiling the program:
gcc -o dates dates.cpp
dates.cpp: In function `int DayCalculation(int, int, int, int, int, int)':
dates.cpp:67: warning:...

i'm also a bit confused. for example, all of the following code works just fine:
#include <stdio.h>

main()
{
char c[100];
scanf("%s", &c);
printf("test %s", &c);
}
#include <stdio.h>

can C programs use iostream? i've done it in C++, and read that it can be done in C, but i keep getting compilation errors.

#include <iostream>
using namespace std;

main()
{
cout << "test";...