How to fix this? c++ compiler set up

I installed gcc via xcode but I am getting this error when trying to compile the file:

 sanjay$ g++ main.cppUndefined symbols for architecture x86_64:"Fraction::Fraction(int, int)", referenced from:      MathAssignTest()     in cck2LKpO.o      BinaryMathTest()     in cck2LKpO.o      RelationTest()     in cck2LKpO.o      BasicTest()    in cck2LKpO.o"Fraction::operator/=(Fraction const&)", referenced from:      MathAssignTest()     in cck2LKpO.o"Fraction::operator-=(Fraction const&)", referenced from:      MathAssignTest()     in cck2LKpO.o"Fraction::operator*=(Fraction const&)", referenced from:      MathAssignTest()     in cck2LKpO.o"Fraction::operator--(int)", referenced from:      MathAssignTest()     in cck2LKpO.o"Fraction::operator--()", referenced from:      MathAssignTest()     in cck2LKpO.o"Fraction::operator+=(Fraction const&)", referenced from:      MathAssignTest()     in cck2LKpO.o"Fraction::operator++(int)", referenced from:      MathAssignTest()     in cck2LKpO.o"Fraction::operator++()", referenced from:      MathAssignTest()     in cck2LKpO.o"operator/(Fraction const&, Fraction const&)", referenced from:      BinaryMathTest()     in cck2LKpO.o"operator==(Fraction const&, Fraction const&)", referenced from:      RelationTest()     in cck2LKpO.o"operator>=(Fraction const&, Fraction const&)", referenced from:      RelationTest()     in cck2LKpO.o"operator>(Fraction const&, Fraction const&)", referenced from:      RelationTest()     in cck2LKpO.o"operator<=(Fraction const&, Fraction const&)", referenced from:      RelationTest()     in cck2LKpO.o"operator<<(std::basic_ostream<char, std::char_traits<char> >&, Fraction const&)", referenced from:      MathAssignTest()     in cck2LKpO.o      BinaryMathTest()     in cck2LKpO.o      RelationTest()     in cck2LKpO.o      BasicTest()    in cck2LKpO.o"operator<(Fraction const&, Fraction const&)", referenced from:      RelationTest()     in cck2LKpO.o"operator-(Fraction const&, Fraction const&)", referenced from:      BinaryMathTest()     in cck2LKpO.o"operator*(Fraction const&, Fraction const&)", referenced from:      BinaryMathTest()     in cck2LKpO.o"operator!=(Fraction const&, Fraction const&)", referenced from:      RelationTest()     in cck2LKpO.o"operator+(Fraction const&, Fraction const&)", referenced from:      BinaryMathTest()     in cck2LKpO.o"operator>>(std::basic_istream<char, std::char_traits<char> >&, Fraction&)", referenced from:      BasicTest()    in cck2LKpO.old: symbol(s) not found for architecture x86_64collect2: ld returned 1 exit status

How do i fix this?I am pretty sure my g++ compiler has been set up properly as it works for files in a different folders. PLease help me out with this..I am a beginner in this language and am trying my best to understand.