关于 error LNK2001: unresolved external symbol "public: __thiscall Genome::Genome(void)"的解决

源代码为

class Genome
{
  public:
	  friend class GenAlg; //种群全部基因
      friend class GenEngine;
	  Genome()  
	  Genome(vector vec , double f)
	 {
		  vecGenome=vec;
		  fitness=f;
	  }
	 
	 
  private:
      vector vecGenome; 
	  double fitness;
};

编译后提示

error LNK2001: 
				unresolved external symbol "public: __thiscall Genome::Genome(void)" (??0Genome@@QAE@XZ)

修改代码为

class Genome
{
  public:
	  friend class GenAlg; //种群全部基因
      friend class GenEngine;
	  Genome()  /*没加这个花括号的话会有
				function operation.obj : error LNK2001: 
				unresolved external symbol "public: __thiscall Genome::Genome(void)" (??0Genome@@QAE@XZ)提示*/
	  {
	  };
	  Genome(vector vec , double f)
	 {
		  vecGenome=vec;
		  fitness=f;
	  }
	 
	 
  private:
      vector vecGenome; 
	  double fitness;
};

之后就没有错误提示了