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Views: 1772 | Replies: 15
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Join Date: Sep 2005
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Junior Poster
Okay Ive made a bunch of single use calculator programs (one for addition, subtraction, mutiplication, and division).
Addition Code
Subtraction
Multiplication
Division
My question is how do I combine these all into one program. Id ask please enter + - * or /. And then make an if statement ....if "symbol" ==x multiply. Is that the right logic or is there a much easier way to do this. And how would I right that if statement. Thanks youve helped me a lot lately guys. -Nick
Addition Code
#include <iostream>
using namespace std;
int main()
{
cout << "Please enter 2 numbers to be added ";
int a;
int b;
cin >> a;
cout << "\n num1: " << a << endl;
cin >> b;
cout << " \n num2: " << b << endl;
cout << " \n a + b = " << a + b << endl;
cout << "Press the enter key to exit";
cin.ignore(numeric_limits<streamsize>::max(), '\n');
cin.get();
return 0;
}Subtraction
// Division Calculator
#include <iostream>
using namespace std;
int main()
{
cout << "Please enter two numbers to be divided: ";
int a;
int b;
cin >> a;
cout << "\n num1: " << a << endl;
cin >> b;
cout << "\n num2: " << b << endl;
cout << "\n a / b = " << a / b << endl;
cin.ignore(numeric_limits<streamsize>::max(), '\n');
cin.get();
return 0;
}Multiplication
//Multiplication Calculator
#include <iostream>
using namespace std;
int main()
{
cout << "Please enter two numbers to be multiplied: ";
int a;
int b;
cin >> a;
cout << "\n num1: " << a << endl;
cin >> b;
cout << "\n num2: " << b << endl;
cout << "\n a x b = " << a * b << endl;
cin.ignore(numeric_limits<streamsize>::max(), '\n');
cin.get();
return 0;
}Division
// Subtraction Calculator
#include <iostream>
using namespace std;
int main()
{
cout << "Please enter 2 numbers to be subtractred";
int a;
int b;
cin >> a;
cout << "\n num1: " << a << endl;
cin >> b;
cout << "\n num2: " << b << endl;
cout << "\n a - b = " << a - b << endl;
cout << "Press the enter key to exit";
cin.ignore(numeric_limits<streamsize>::max(), '\n');
cin.get();
return 0;
}My question is how do I combine these all into one program. Id ask please enter + - * or /. And then make an if statement ....if "symbol" ==x multiply. Is that the right logic or is there a much easier way to do this. And how would I right that if statement. Thanks youve helped me a lot lately guys. -Nick
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Join Date: Sep 2004
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The only difference is asking for an operator too:
#include <iostream>
using namespace std;
int main()
{
int a, b;
char op;
cin>> a >> ws >> op >> b;
if ( op == '+' )
cout<< a + b <<'\n';
else if ( op == '-' )
cout<< a - b <<'\n';
else if ( op == '*' )
cout<< a * b <<'\n';
else if ( op == '/' )
cout<< a / b <<'\n';
else
cerr<<"Invalid operation\n";
} Member of: Beautiful Code Club.
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Junior Poster
Thanks a lot Narue.
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Junior Poster
#include <iostream>
using namespace std;
int main()
{
int a;
int b;
char op;
cout << "Please enter one number thne press enter then enter the second number";
cin >> a;
cout << "\n Num1: " << a << endl;
cin >> b;
cout << "\n Num2: " << b << endl;
cout << "\n Now enter + to add....- to subtract....* to multiply....or / to divide";
cin >> op;
if ( op == "+" )
cout << a + b << '\n;
else if ( op == "-")
cout << a - b << '\n;
else if ( op == "*" )
cout << a * b << '\n;
else if ( op == "/" )
cout << a / b << '\n;
else cout << "Invalid Operation\n";
Well heres my code and Im getting a lot of errors.
1.
IM not sure if theres the quotation marks or the thing on the same key around the operation sign?
if ( op == "+" )
cout << a + b << '\n; •
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Join Date: Feb 2005
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Posting Pro in Training
If op is a single char, then you need to compare with single quotes '+'
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Junior Poster
im really new to C++ and I never used char to declare a variable. I always used int but that wont work now cause int only works for numbers. Now what do you mean by char op; being a single char
BTW does char stand for character
BTW does char stand for character
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Junior Poster
#include <iostream>
using namespace std;
int main()
{
int a;
int b;
char op;
cout << "Please enter one number thne press enter then enter the second number";
cin >> a;
cout << "\n Num1: " << a << endl;
cin >> b;
cout << "\n Num2: " << b << endl;
cout << "\n Now enter + to add....- to subtract....* to multiply....or / to divide";
cin >> op;
if ( op == '+' )
cout << a + b << endl;
else if ( op == '-')
cout << a - b << endl;
else if ( op == '*' )
cout << a * b << endl;
else if ( op == '/' )
cout << a / b << endl;
else cout << "Invalid Operation\n";
cin.ignore(numeric_limits<streamsize>::max(), '\n');
cin.get();
return 0;
}K Thans for all the help guys I dont know what I would do without you. One question though Narue in the code snippet u gave me it was '\n; after the if statment. however I got like 4 compiler errors when trying to compile it so I jsut changed it to endl;......What does the '\n; do and why did my compiler say it was an error?
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>BTW does char stand for character
Yes.
>What does the '\n; do and why did my compiler say it was an error?
'\n' is an escape character that means newline. It's basically does the same thing as pressing Return on your keyboard. You shouldn't be getting errors with it though, especially since endl uses it for half of the operation:
Notice that endl also flushes the stream, which can be expensive if done often. That's why I prefer using '\n' explicitly and let the C++ flush the stream for me except when I really need it. I would imagine that something else was causing the problem, but you can use this test program to see:
Yes.
>What does the '\n; do and why did my compiler say it was an error?
'\n' is an escape character that means newline. It's basically does the same thing as pressing Return on your keyboard. You shouldn't be getting errors with it though, especially since endl uses it for half of the operation:
template <typename T, typename Traits>
basic_ostream<T, Traits>& endl ( basic_ostream<T, Traits>& out )
{
out.put ( out.widen ( '\n' ) );
out.flush();
}#include <iostream>
int main()
{
std::cout<< 12345 <<'\n';
} Member of: Beautiful Code Club.
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Junior Poster
basic_ostream<T, Traits>& endl ( basic_ostream<T, Traits>& out )
gives me an invalid syntax error.
gives me an invalid syntax error.
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>gives me an invalid syntax error.
You're not meant to understand what's going on with that function or try to compile it. That code was strictly explanatory for future reference (and yes, it is correct. You're just trying to compile it incorrectly). The second example was for you to compile so that we could figure out what you're doing wrong so that '\n' fails to compile.
You're not meant to understand what's going on with that function or try to compile it. That code was strictly explanatory for future reference (and yes, it is correct. You're just trying to compile it incorrectly). The second example was for you to compile so that we could figure out what you're doing wrong so that '\n' fails to compile.
Member of: Beautiful Code Club.
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