Function C

#include 
int main()
{
    int   old_number= 1;
    int   current_number = 1;
    int   next_number;
    while (current_number < 100) {
        printf("%d\n", current_number);
        next_number = current_number + old_number;
        old_number = current_number;
        current_number = next_number;
    }
    return (0);
}