Help with C++ menu coding for Multiplication Table and Calculator?

Here's what I have at the moment:





#include %26lt;iostream%26gt;


#include %26lt;conio.h%26gt;





using namespace std;





int main()





{


char choice;


choice = toupper(choice);


int tableno;


int numoflines;


int multable;


int firstno;


int secondno;


char operation;


int calculation;


int i;





do


{


system(';CLS';);


cout%26lt;%26lt;';Do you want to create a Multiplication Table (M)';;


cout%26lt;%26lt;endl;


cout%26lt;%26lt;';Or perfrom a Calculation (C)?';;


cout%26lt;%26lt;endl;


cin%26gt;%26gt;choice;





while (choice !='M' || choice !='C')





cout%26lt;%26lt;';Please enter M or C only';;


cout%26lt;%26lt;endl;


cin%26gt;%26gt;choice;








switch (choice)


{


case 'M':


system(';CLS';);


cout%26lt;%26lt;';Please enter the Multiplication table number between 1 and 20';;


cout%26lt;%26lt;endl;


cin%26gt;%26gt;tableno;


if (tableno %26lt;1 || tableno %26gt;20)


{


cout%26lt;%26lt;';Multiplication table number should be between 1 and 20 only';;


cout%26lt;%26lt;endl;


cin%26gt;%26gt;tableno;


}


else


{


cout%26lt;%26lt;';Please enter the number of Lines between 1 and 15';;


cout%26lt;%26lt;endl;


cin%26gt;%26gt;numoflines;


}


if (numoflines %26lt;1 || numoflines %26gt;15)


{


cout%26lt;%26lt;';Number of Lines is not btetween 1 and 15';;


cout%26lt;%26lt;endl;


cin%26gt;%26gt;numoflines;


}


else


for (i=1; i%26lt;=numoflines; i++)


{


cout%26lt;%26lt;i;


cout%26lt;%26lt;'; x ';;


cout%26lt;%26lt;numoflines;


cout%26lt;%26lt;'; = ';;


multable = numoflines*i;


cout%26lt;%26lt;multable;


cout%26lt;%26lt;endl;


break;


}





case 'C':


system(';CLS';);


cout%26lt;%26lt;';Please enter your First number between 0 and 1000';;


cout%26lt;%26lt;endl;


cin%26gt;%26gt;firstno;


if (firstno %26lt;0 || firstno %26gt;1000)


{


cout%26lt;%26lt;';First number is not between 0 and 1000';;


cout%26lt;%26lt;endl;


cin%26gt;%26gt;firstno;


}


else


{


system(';CLS';);


cout%26lt;%26lt;';Please enter the Operator (+, -, *, / or %';;


cout%26lt;%26lt;endl;


cin%26gt;%26gt;operation;


system(';CLS';);


calculation = firstno; operation; secondno;


cout%26lt;%26lt;calculation;


}


if (operation ='%')


{


system(';CLS';);


cout%26lt;%26lt;';This is a modulus division which displays the remainder of an integer division';;


cout%26lt;%26lt;endl;


break;


}


}


}





return 0;


}Help with C++ menu coding for Multiplication Table and Calculator?
for my testing. it goes well