Use reference as a return type : reference « Data Types « C++ Tutorial

1. C++ Tutorial
2. Data Types
3. reference

#include <iostream.h>

int& Fn(int * p,int i);

main()
{
       const int S=4;
       int  a[S] = {1,3,5,-1};
       for (int j = 0; j<S; j++)
       {
               Fn(a,j) += 1;
               cout << Fn(a,j) << endl;
       }
       return 0;
}

int& Fn(int * p,int i){        
    return p[i];
}

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