#include <iostream>
#include <ctime>
 
using namespace std;
 
int DoMenu();
void addition(int random1, int random2);
void subtraction(int random1, int random2);
void multiplication(int random1, int random2);
void division(int random1, int random2);
 
int main()
{  
    int random1, random2;
    srand(time(0));
 
    int choice;
 
    do
    {
        random1 = 1+(rand()%20); // from 1-20
        random2 = 1+(rand()%20); // from 1-20
 
        choice = DoMenu();
 
        switch (choice)
        {
            case 0: cout << endl;                     break;
            case 1: addition(random1,random2);         break;
            case 2: subtraction(random1,random2);     break;
            case 3: multiplication(random1,random2); break;
            case 4: 
                {
                    if (random2 == 0)
                        cout << "Error: Division by zero, cannot proceed\n";
                    else
                        division(random1,random2);
                } break;
            default : cout << "Error in input\n\n"; break;
        }
 
    } while (choice != 0);
 
    return 0; 
}
 
int DoMenu()
{
    int MenuChoice;
        cout << "(1)Addition\n";
        cout << "(2)Subtraction\n";
        cout << "(3)Multiplication\n";
        cout << "(4)Division\n";
        cout << "(0)Quit\n";
        cout << "-----------------\n";
        cout << "Choice: ";
    cin >> MenuChoice;
    return MenuChoice;
}
 
void addition(int random1, int random2)
{
    int answer;
 
    cout << "\n" << random1 << " + " << random2 << " = ";
    cin >> answer;
 
    if (answer == (random1+random2))
        cout << "Congratulations\n\n";
    else
        cout << "Incorrect\n\n";
}
 
void subtraction(int random1, int random2)
{
    int answer;
 
    cout << "\n" << random1 << " - " << random2 << " = ";
    cin >> answer;
 
    if (answer == (random1-random2))
        cout << "Congratulations\n\n";
    else
        cout << "Incorrect\n\n";
}
 
void multiplication(int random1, int random2)
{
    int answer;
 
    cout << "\n" << random1 << " * " << random2 << " = ";
    cin >> answer;
 
    if (answer == (random1*random2))
        cout << "Congratulations\n\n";
    else
        cout << "Incorrect\n\n";
}
 
void division(int random1, int random2)
{
    int answer;
 
    cout << "\n" << random1 << " / " << random2 << " = ";
    cin >> answer;
 
    if (answer == (random1/random2))
        cout << "Congratulations\n\n";
    else
        cout << "Incorrect\n\n";
}

#include<iostream>
usingnamespace std;
int Add(int x, int y);
int Subtract(int x, int y);
int Times (int x, int y);
int Divide (int x, int y);
int Remainder (int x, int y);
int main()
{
int a,b,c,d,x=0;
while (x!=77){
cout<<"1:Addition\n2:Subtraction\n3:Multiplication\n4:Division\n5:Quit"<<endl;
cin>>x;
a=rand()%19 + 1;
b=rand()%19 + 1;
switch(x)
{
case 1: 
cout<<a<<"+"<<b<<"=??";
d=Add(a,b);
break;
case 2:
cout<<a<<"-"<<b<<"=??";
d=Subtract(a,b);
break;
case 3:
cout<<a<<"*"<<b<<"=??";
d=Times(a,b);
break;
case 4:
cout<<a<<"/"<<b<<"=??";
d=Divide(a,b);
break;
case 5:
return 0;
break;
}//end switch(x)
cin>>c;
if (c==d)
cout<<"Congratulations...You are Correct";
else
cout<<"Incorrect...The correct answer is "<<d;
if (x==4)
cout<<"\nwith a remainder of "<<Remainder(a,b);
cout<<endl<<endl;
}//end while(x)
}
int Add(int x, int y)
{
int z;
z=x+y;
return z;
}
int Subtract (int x, int y)
{
int z;
z=x-y;
return z;
}
int Times (int x, int y)
{
int z;
z=x*y;
return z;
}
int Divide (int x, int y)
{
int z;
z=x/y;
return z;
}
int Remainder (int x, int y)
{
int z;
z=x%y;
return z;
}