How to solve this error?of terminal

Question

#include<iostream>
#include<cstdlib>
#include<cmath>

using namespace std;
int round(double number);
int main()
 {
  double doublevalue;
   char ans;
    do
    {
    cout << "Enter the double value:";
       cin >> doublevalue;
     cout << "Rounded that number is"<<round(doublevalue)<<endl;
     cout << "Again?(y/n)";
     cin >> ans;
      }while(ans=='y' ||ans=='Y');
        cout << "End of testing.\n";
       return 0;
         }
        int round(double number)
      {
      return static_cast<int>(floor(number+0.5));
     }

error is as below:

 roundoff.cpp:6:24: error: new declaration ‘int round(double)’
  int round(double number);
                    ^
 In file included from /usr/include/features.h:374:0,
             from /usr/include/x86_64-linux-gnu/c++/4.8/bits/os_defines.h:39,
             from /usr/include/x86_64-linux-gnu/c++/4.8/bits/c++config.h:426,
             from /usr/include/c++/4.8/iostream:38,
             from roundoff.cpp:1:
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:309:1: error: ambiguates     old declaration ‘double round(double)’
 __MATHCALLX (round,, (_Mdouble_ __x), (__const__));

^ roundoff.cpp: In function ‘int round(double)’: roundoff.cpp:22:24: error: new declaration ‘int round(double)’ int round(double number) ^ In file included from /usr/include/features.h:374:0, from /usr/include/x86_64-linux-gnu/c++/4.8/bits /os_defines.h:39, from /usr/include/x86_64-linux-gnu/c++/4.8/bits /c++config.h:426, from /usr/include/c++/4.8/iostream:38, from roundoff.cpp:1: /usr/include/x86_64-linux-gnu/bits/mathcalls.h:309:1: error: ambiguates old declaration ‘double round(double)’ MATHCALLX (round,, (Mdouble __x), (__const)); ^

See [`std::round`](http://en.cppreference.com/w/cpp/numeric/math/round). To be fair, C++ allows `cmath` to put `round` in the global namespace, so you could get the same error without `using namespace std;`. — juanchopanza, Aug 03 '16 at 09:06

score 1 · Accepted Answer · edited Aug 12 '16 at 04:16

1

You must change the name of your function round because cmath already defines a method called round with same signature causing the ambiguity. Change the name to my_round(double number) instead of round and it will work.

edited Aug 12 '16 at 04:16

doobop

4,465
2
28
39

answered Aug 03 '16 at 13:20

Sami

56
5

How to solve this error?of terminal

1 Answers1