c++ - Variable undeclared and primary expression expected -

#include <cstdlib> #include <iostream>  using namespace std;  int main(int argc, char *argv[]) {     int amount;     int newamount;     int interestrate;     int initialamount;      cout << "please enter dollar amount. ";      cin >> amount;                 cout << "please enter interest rate(e.g., 9 percent shouold entered 9.0). ";     cin >> interestrate;      newamount = futurevalue(amount,interestrate);      cout << "the new dollar amount ", newamount;      futurevalue(int initialamount, int interestrate);     int finalamount;     finalamount = (1 + interestrate/100) * initialamount;     return finalamount;      system("pause");     return exit_success; } 

i'm getting "19 `futurevalue' undeclared (first use function)" "23 expected primary-expression before "int" " , "23 expected primary-expression before "int" " again

i recommend declaring function, , removing "declaration" line 23. can't declare function that, , if could, call before declared causes error

futurevalue(int initialamount, int interestrate) // place whole thing before main {      int finalamount;      finalamount = (1 + interestrate/100) * initialamount;      return finalamount; } 

or

futurevalue(int initialamount, int interestrate); // before main // later futurevalue(int initialamount, int interestrate) // place after main {      int finalamount;      finalamount = (1 + interestrate/100) * initialamount;      return finalamount; }