This week in my AP Biology class we are doing a thing on Drosophila Flies. The experiment involves making a BOATLOAD of Punnett Squares.

After a few minutes of doing them, I got kind of bored and made a quick program to make punnett squares for me, as well as analyze the punnet square. Later I added more functions to make things easier for me.

I just wanted to post it here to get a critique of my code, I'm kind of just starting out so I wanted to know how I'm doing. Don't take it easy on me though.
Here's the code:
Code:
#include <iostream>

using namespace std;

void boxes(char a, char b, char c, char d);
void analyze(char a2, char b2, char c2, char d2);


int main()
{
    char a1,a2,a3,a4,resp;
    resp = 'y';
    cout<<"Punnet Squarer\n V1.0"<<endl;
while(resp == 'y'){
    cout<<"enter first letter for top row A/a"<<endl;
    cin>>a1;
    cout<<"enter second letter for top row A/a"<<endl;
    cin>>a2;
    cout<<"enter first letter for side column A/a"<<endl;
    cin>>a3;
    cout<<"enter second letter for side comumn A/a"<<endl;
    cin>>a4;

    boxes(a1,a2,a3,a4);
    analyze(a1,a2,a3,a4);

    cout<<"\n\n";

    cout<<"do another punnett square? y/n"<<endl;
    cin>>resp;
}

    return 0;
}

void boxes(char a, char b, char c, char d) {

    if(a=='a' && c=='A'){
        a='A';
        c='a';
    }
    if(b=='a' && c=='A'){
        b='A';
        c='a';
    }
    if(a=='a' && d=='A'){
        a='A';
        d='a';
    }
    if(b=='a' && d=='A'){
        b='A';
        d='a';
    }
    cout<<"\n\n";
    cout<<"      ";
    cout<<a<<c;
    cout<<" ";
    cout<<"|";
    cout<<" ";
    cout<<b<<c;
    cout<<endl;

    cout<<"      ";
    cout<<"--------"<<endl;

    cout<<"      ";
    cout<<a<<d;
    cout<<" ";
    cout<<"|";
    cout<<" ";
    cout<<b<<d;
    cout<<endl;
}

void analyze(char a2, char b2, char c2, char d2){
 int count, homdcount, homrcount, hetrocount,homd,homr,hetro;
 count=0;
 homdcount=0;
 homrcount=0;
 hetrocount=0;
 homd=0;
 homr=0;
 hetro=0;
                 /*Analysis section START*/
               /* Analyze top left corner */
    if(a2=='A' && c2=='A' || a2=='A' && c2=='a' || a2=='a' && c2=='A' ){
    ++count;
    }
              /* Analyze top right corner */
    if(b2=='A' && c2=='A' || b2=='A' && c2=='a' || b2=='a' && c2=='A' ){
    ++count;
    }
              /* Analyze bottom left corner */
    if(a2=='A' && d2=='A' || a2=='A' && d2=='a' || a2=='a' && d2=='A' ){
    ++count;
    }
              /* Analyze bottom right corner */
    if(b2=='A' && d2=='A' || b2=='A' && d2=='a' || b2=='a' && d2=='A' ){
    ++count;
    }
     /*Analyze top left square*/
    if(a2=='A' && c2=='A'){
    ++homdcount;
    }
    else if(a2=='a' && c2=='a'){
    ++homrcount;
    }
    else{
    ++hetrocount;
    }
    /*Analyze top right square*/
    if(b2=='A' && c2=='A'){
    ++homdcount;
    }
    else if(b2=='a' && c2=='a'){
    ++homrcount;
    }
    else{
    ++hetrocount;
    }

    /*Analyze bottom left square*/
    if(a2=='A' && d2=='A'){
    ++homdcount;
    }
    else if(a2=='a' && d2=='a'){
    ++homrcount;
    }
    else{
    ++hetrocount;
    }
      /*Analyze bottom right square*/
    if(b2=='A' && d2=='A'){
    ++homdcount;
    }
    else if(b2=='a' && d2=='a'){
    ++homrcount;
    }
    else{
    ++hetrocount;
    }
 switch(hetrocount){
  case 1:
   hetro=25;
   break;
  case 2:
   hetro=50;
   break;
  case 3:
   hetro=75;
   break;
  case 4:
   hetro=100;
   break;
 }
 switch(homrcount){
  case 1:
   homr=25;
   break;
  case 2:
   homr=50;
   break;
  case 3:
   homr=75;
   break;
  case 4:
   homr=100;
   break;
 }
 switch(homdcount){
  case 1:
   homd=25;
   break;
  case 2:
   homd=50;
   break;
  case 3:
   homd=75;
   break;
  case 4:
   homd=100;
   break;
 }
 /*Analysis section END*/
 /*Show results of Analysis*/
 switch(count){
  case 1:
   cout<<"25% Dominant"<<endl;
   break;
  case 2:
   cout<<"50% Dominant"<<endl;
   break;
  case 3:
   cout<<"75% Dominant"<<endl;
   break;
  case 4:
   cout<<"100% Dominant"<<endl;
   break;
 }
   cout<<"analysis:"<<endl;
   cout<<"This Generation is "<<homd<<"% Homozygous Dominant"<<endl;
   cout<<"This Generation is "<<homr<<"% Homozygous recessive"<<endl;
   cout<<"This Generation is "<<hetro<<"% Heterozygous"<<endl;
 }
Thanks guys.