Merging an array in c++

Merging an array 

                                                                                                    //merging//

 #include<iostream.h>                                                          

 void merge(int[], int, int[],int,int[]);        
                              

 void main()                                                                   

{                                                                              

     int A[50], B[50], C[50], MN=0, M, N;                                          

     cout<<" how many elements do u want to create first array with?..";       

     cin>>M;                                                                     

     cout<<"\n enter first array's elements [ascending] ...";     
                 

     for( int i=0; i<M; i++)                                                       

     {                                                                               

          cin>>A[i];                                                                  

     }          
                                                                   

      cout<<"how many elements do u want to create second array with ?....";     

      cin>>N;                                                                       

      MN = M + N  ;                                                                 

      cout<<"\n enter second array elements[descending]...\n";   
                  

      for( i=0; i<N; i++)                                                         

      {                                                                                . 

          cin>> B[i];                                                                .

      }       
                                                                       

       merge(A,M,B,N,C);

       cout<<”\n the merged array is as shown below…..\n”;

       for(i=0; i<MN; i++)

           cout<<C[i]<<”  “;

       cout<<endl;

 }

   void merge(int A[], int M, int B[], int N, int C[])

  {

          int a,b,c;

          for(a=0; b=N-1; c=0; a<M && b>=0;)

          {

                 if(A[a]<= B[b])              C[c++]=A[a++];

                           elseC[c++]=B[b--];

          }

           if(a<m)

                     {

                                        while(a<m)

                                        C[c++]=A[a++];

                      }

           else

                       {

                                     while(b>=0)

                                             C[c++]=B[b--];

                        }

   }