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POc++ how to solve my memory leak?
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copied!<p>Consider the following implemntation of a Binary class representation of an integer:</p> <pre><code>class Binary { private: int *digits; int first1; public: Binary() { digits = new int[128]; digits[0]=0; first1=0; } ~Binary() { cout<<"deleting"<<endl; delete [] digits; } Binary(const Binary& b){ digits = new int[128]; memcpy(digits,b.digits,128*sizeof(int)); first1=b.first1; } explicit Binary(double x){ int n=(int)x,i; digits = new int[128]; for (i=0; n ; i++,n>>=1) digits[i]=(n & 1)? 1:0; first1=i-1; } Binary& operator =(const Binary& b){ if (this==&b) return *this; memcpy(digits,b.digits,128*sizeof(int)); first1=b.first1; return *this; } Binary(int n) { int i; digits = new int[128]; for (i=0; n ; i++,n>>=1) digits[i]=(n & 1)? 1:0; first1=i-1; } void print() { for (int i=first1; i>=0 ; i--) cout<<digits[i]; cout<<endl; } operator int() { int x = 1,sum=0; for (int i=0; i<=first1 ; i++,x<<=1) sum+=digits[i]*x; return sum; } Binary& operator +(Binary& a) { int overflow = 0; Binary* b1=new Binary(); int max = a.first1>this->first1? a.first1 : this->first1,bit; for (int i=0; i<=max ; i++) { bit=a.digits[i]+this->digits[i]+overflow; overflow=0; if (bit>1) overflow=1; b1->digits[i]=bit%2; } return *b1; } }; </code></pre> <p>and the main using it:</p> <pre><code>int main() { Binary b(91); int x=9; Binary *b2=new Binary(); *b2=b+x; x=*b2; b2->print(); cout<<" = "<<x; cin>>x; } </code></pre> <p>lets talk about the line:</p> <pre><code>*b2=b+x; </code></pre> <p>first the compiler implicitly allocates a new binary instance for int x, then using it as a paramater for the addition, then creates a new binary instance for the addition result and copies it bit by bit to *b2.</p> <p>The problem is, that if you run this code, it only prints deleting ONCE, while there were 2 objects created for the execution of the command. apparently there's a leak comes from the addition code, in which i explicitly created a new object to return the result.</p> <p><strong>Q1</strong>: am i correct?</p> <p><strong>Q2</strong>: what can i do to overcome this?</p> <p><strong>EDIT</strong>: The answer and more about the topic of operator overloading can be found <a href="https://stackoverflow.com/questions/4421706/operator-overloading">here</a></p>

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