C++ code

[altunozara]

I am trying to make a simple calculator and it wont

#include <stdlib.h>
#include <iostream>
using namespace std;
int mult ( int x, int y );
int main()
{
int x;
int y;
int calc;
int a;
int b;
cout<<"Please choose which calculator function you would like to use: \n 1.Multiplication\n 2.Addition\n 3.Subtraction\n 4.Division\n";
cin>> calc;
cin.ignore();

if ( calc == 1 )

cout<<"Please insert any two numbers to be multiplied together: ";
cin>> x >> y;
cin.ignore();
cout<<"The product of your two numbers is "<< mult ( x, y ) <<"\n";
cin.get();
}
int mult ( int x, int y )
{
return x * y;
}
else if ( calc == 2 )
cout<<"Please insert two numbers. The second will be subtracted from the first: ";
cin>> a >> b;
cin.ignore();
cout<<"The number"<< ( a ) <<"minus"<< ( b ) <<"is"<< subt ( a,b ) <<"\n;
cin.get();
}

that is my code

i think there is something wrong in this area

else if ( calc == 2 )
cout<<"Please insert two numbers. The second will be subtracted from the first: ";
cin>> a >> b;
cin.ignore();
cout<<"The number"<< ( a ) <<"minus"<< ( b ) <<"is"<< subt ( a,b ) <<"\n;
cin.get();

please tell me what is wrong i spent a long time on this code.

[FreePlay]

Did you ever make the subt function? Because it's not in the code you posted.

[altunozara]

hmm how do i do that....

int subt ( int a, int b );

?

and i get an error when trying top compile the code above it puts this like in red

else if ( calc == 2 )

and has this error "expected unqualified-id before "else"

[FreePlay]

oh.
wow.
Amazed I didn't see it before

int main()
{
int x;
int y;
int calc;
int a;
int b;
cout<<"Please choose which calculator function you would like to use: \n 1.Multiplication\n 2.Addition\n 3.Subtraction\n 4.Division\n";
cin>> calc;
cin.ignore();

if ( calc == 1 )

cout<<"Please insert any two numbers to be multiplied together: ";
cin>> x >> y;
cin.ignore();
cout<<"The product of your two numbers is "<< mult ( x, y ) <<"\n";
cin.get();
}
int mult ( int x, int y )
{
return x * y;
}
else if ( calc == 2 )
cout<<"Please insert two numbers. The second will be subtracted from the first: ";
cin>> a >> b;
cin.ignore();
cout<<"The number"<< ( a ) <<"minus"<< ( b ) <<"is"<< subt ( a,b ) <<"\n;
cin.get();
}

1. If your 'if' statements will determine that MORE THAN ONE line of code is going to run, you need to enclose the code in brackets.
2. You ended your 'main' function without a return value.
3. You used 'subt' but never made any *code* for it.
4. You attempted to embed 'mult' in 'main'. You... should never do that. Ever.
5. You've got unnecessary extra variables. If your code's flow never uses the same variable twice to get input, just use the same variable in every flow path (i.e. if it's used in the 'if' and 'else' parts of an 'if' statement, use the same variable to get input in both).

#include <iostream>
using namespace std;
int mult ( int x, int y );
int subt ( int x, int y ); // definition!!
int main()
{
int x;
int y;
int calc;
cout<<"Please choose which calculator function you would like to use: \n 1.Multiplication\n 2.Addition\n 3.Subtraction\n 4.Division\n";
cin>> calc;
cin.ignore();

if ( calc == 1 ) { // bracket!!

cout<<"Please insert any two numbers to be multiplied together: ";
cin>> x >> y;
cin.ignore();
cout<<"The product of your two numbers is "<< mult ( x, y ) <<"\n";
cin.get();
}
else if ( calc == 2 ) { // bracket!!
cout<<"Please insert two numbers. The second will be subtracted from the first: ";
cin>> x >> y;
cin.ignore();
cout<<"The number"<< ( x ) <<"minus"<< ( y ) <<"is"<< subt ( x,y ) <<"\n;
cin.get();
}

int mult ( int x, int y )
{
return x * y;
}

int subt ( int x, int y ) // code!!
{
return x - y;
}

[altunozara]

#include <iostream>
using namespace std;
int mult ( int x, int y );
int subt ( int x, int y ); // definition!!
int main()
{
int x;
int y;
int calc;
cout<<"Please choose which calculator function you would like to use: \n 1.Multiplication\n 2.Addition\n 3.Subtraction\n 4.Division\n";
cin>> calc;
cin.ignore();

if ( calc == 1 ) { // bracket!!

cout<<"Please insert any two numbers to be multiplied together: ";
cin>> x >> y;
cin.ignore();
cout<<"The product of your two numbers is "<< mult ( x, y ) <<"\n";
cin.get();
}
else if ( calc == 2 ) { // bracket!!
cout<<"Please insert two numbers. The second will be subtracted from the first: ";
cin>> x >> y;
cin.ignore();
cout<<"The number"<< ( x ) <<"minus"<< ( y ) <<"is"<< subt ( x, y ) <<"\n";
cin.get();
}
int mult ( int x, int y )
{
return x * y;
}
int subt ( int x, int y ) // code!!
{
return x - y;
}__________________

but now theres an error on the line i did in bold
it comes with this error "a function-definition is not allowed here before '{' token"

[Archaemic]

...why the hell would you declare a function to do what an operator can do?

[altunozara]

Please just tell me how to fix it

[Archaemic]

cout<<"The product of your two numbers is "<< mult ( x, y ) <<"\n";

could easily be

cout<<"The product of your two numbers is "<< (x*y) <<endl;

etc.

[M7thCC]

Moved to development. Good luck with your code.

[altunozara]

ty but how comke theres that error

[Darkhunter]

Look at my code. It seems simpler than yours.

Spoiler for My code:

#include <iostream>
#include <cmath>
#include <cstring>
using namespace std;
int main ()
{
//declare variable
char expr;
 
 
double number1, 
number2,
total;
 
//output to the user
cout << "This is a mini calculator. Made By: Darkhunter \n"
<< "Add +\nSubtract -\nMultiply *\nDivide /\nPower ^\n"
<< "\nInput your calculation"<<endl;
 
while (true) 
{
cin >>number1 >> expr >> number2;
switch (expr)
{
case '+':
total = number1 + number2;
cout << number1 <<" + " << number2 << " = " << total <<endl;
break;
 
case '*':
total = number1 * number2;
cout << number1 <<" * " << number2 << " = " << total <<endl;
break;
 
case '/':
total = number1 / number2;
cout << number1 <<" / " << number2 << " = " << total <<endl;
break;
 
case '-':
total = number1 - number2;
cout << number1 <<" - " << number2 << " = " << total <<endl;
break;
 
case '^':
cout << number1 <<" ^ " << number2 << " = " << pow (number1, number2) <<endl;
break;
 
default:
cout << "This is an invalid input" <<endl;
 
}
}
system ("PAUSE");
return 0;
}

[altunozara]

OMFG I FIXED IT! ON YM OWN! i read the error and it said something about it being in main and i thaught i should maybe put in another } to end the main...it worked!
-= Double Post =-
yeh but i dont get how that code works...

[Bronx]

you forgot your closing bracket for the main function.

int main()
{ // bracket!!
	int x;
	int y;
	int calc;
	cout<<"Please choose which calculator function you would like to use: \n 1.Multiplication\n 2.Addition\n 3.Subtraction\n 4.Division\n";
	cin>> calc;
	cin.ignore();

	if ( calc == 1 )
	{ // bracket!!
		cout<<"Please insert any two numbers to be multiplied together: ";
		cin>> x >> y;
		cin.ignore();
		cout<<"The product of your two numbers is "<< mult ( x, y ) <<"\n";
		cin.get();
	} // closing bracket!!
	else if ( calc == 2 )
	{ // bracket!!
		cout<<"Please insert two numbers. The second will be subtracted from the first: ";
		cin>> x >> y;
		cin.ignore();
		cout<<"The number"<< ( x ) <<"minus"<< ( y ) <<"is"<< subt ( x,y ) <<"\n";
		cin.get();
	} // closing bracket!!
} // closing bracket!! This is what you forgot

int mult ( int x, int y )
{
	return x * y;
}

int subt ( int x, int y ) // code!!
{
	return x - y;
}

Notice I indented your code. Now you can easily see how each opening and closing bracket line-up, making it easy to see if you forgot one.

Edit - seemed you fixed it... BTW, the indentation on these forums are really big!

[altunozara]

WOOH! Ive done addition subtraction multiplication and division!

except ...once you choose which..and enter the numbers it tells you but you vcant enter more in...

how can i make it loop something...

[FreePlay]

'do'...'while' perhaps...

[altunozara]

hmmm is there a way to make it so like once youve entered the two numbers it goes back to the choose your option of which calc type and then you enter again and it goes back again...? ive tried while and do.. while

[FreePlay]

obviously not hard enough...

put a 'do {' before the first cout, and a '}' before the main function's closing bracket.

[altunozara]

i did this

#include <stdlib.h>
#include <iostream>
using namespace std;
int mult ( int x, int y );
int addi ( int x, int y );
int subt ( int x, int y );
int divi ( int x, int y );
int main()
{ // bracket!!
int x;
int y;
int calc;
int restart;
do {
cout<<"Please choose which calculator function you would like to use: \n 1.Multiplication\n 2.Addition\n 3.Subtraction\n 4.Division\n";
cin>> calc;
cin.ignore();
}
while
if ( calc == 1 )
{ // bracket!!
cout<<"Please insert any two numbers to be multiplied together: ";
cin>> x >> y;
cin.ignore();
cout<<"The product of your two numbers is "<< mult ( x, y ) <<"\n";
cin.get();

} // closing bracket!!

but now i dont know how to make the while do something that says when you choose an option and it gives you the answer it will go and do the "do" any help?

[Archaemic]

Your brackets don't match.

Also, the syntax of your do...while command is wrong.

[altunozara]

how can i fix it...

[Darkhunter]

Originally Posted by altunozara

how can i fix it...

Dude it would be easier if you just buy a c++ book.

[altunozara]

...i just need to know how to loop something ive learned sooo much and i probebly am gonna buy a book :-D but what i wna do is learn how to loop then once ive just elarned that i can do simple text based c++ programs. Im going to improve my calculator and port it to the psp if i can.
-= Double Post =-
t cant i just make a thing that sais something like

if ( x == 1 )
restart;

or something? then i can make it say please enter 1 to restart but i dont know the function to restart the program...

[Archaemic]

while(x == 1) {
//insert code here
}

[JustChris]

Just while (1) would do, because 1 would always be 1.

Also, regarding

int mult ( int x, int y );
int addi ( int x, int y );
int subt ( int x, int y );
int divi ( int x, int y );

This looks like a job for...function pointers!
Maybe this subject is a little too advanced for you now, but it can cut down on redundant code with similar function structures. Try looking into it at some point.

[Raphael]

It was already mentioned that he doesn't need the functions altogether, since it can be done by straight use of the operators.

[altunozara]

so i just use this

while(x == 1) {
//insert code here
}

and somehow once ive done a code and press enter when it would usually exit it does this
while(x == 1) {
//insert code here
}
?

[Archaemic]

The //insert code here is the code that you want to be looped. When you want to exit out of the loop, set x to any value other than 1, and at the end of that instance of the loop, it will cease to loop.

[altunozara]

code #include <stdlib.h> #include <cstdlib> #include <iostream> using namespace std; int mult ( int x, int y ); int addi ( int x, int y ); int subt ( int x, int y ); int divi ( int x, int y ); char addit ( int x, int y ); int answer; int answers; int ext; char ok; int number; int random; int main(int argc, char *argv[]) { // bracket!! int x; int y; int calc; int ext; int restart; int xx = 10; int random_integer = rand(); cout << random_integer << endl; cout<<"Please choose which calculator function you would like to use: \n 1.Multiplication\n 2.Addition\n 3.Subtraction\n 4.Division\n 5.Revision\n 6.Test\n 7.Extras\n#"; cin>> calc; cin.ignore(); if( calc == 1 ) { // bracket!! cout<<"Please insert any two numbers to be multiplied together: "; cin>> x >> y; cin.ignore(); cout<<"The product of your two numbers is "<< mult ( x, y ) <<"\n"; cin>> calc; cin.ignore(); cin.ignore(); cin.get(); } // closing bracket!! else if ( calc == 3 ) { // bracket!! cout<<"Please insert two numbers. The second will be subtracted from the first: "; cin>> x >> y; cin.ignore(); cout<<"The number "<< ( x ) <<" minus "<< ( y ) <<" is "<< subt ( x,y ) <<"\n"; cin.get(); } // closing bracket!! else if ( calc == 2 ) { // bracket!! cout<<"Please insert two numbers which will be added together: "; cin>> x >> y; cin.ignore(); cout<<"The number "<< ( x ) <<" plus "<< ( y ) <<" equals "<< addi ( x,y ) <<"\n"; cin.get(); } // closing bracket!! else if ( calc == 4 ) { // bracket!! cout<<"Please enter two numbers. The first number will be divided by the second: "; cin>> x >> y; cin.ignore(); cout<<"The number "<< ( x ) <<" divided by "<< ( y ) <<" equals "<< divi ( x,y ) <<"\n"; cin.get(); } // closing bracket!! //PUT REVISION BEFORE TEST else if ( calc == 5 ) { // bracket!! cout<<"#TEST#\nAnswer all the questions the best you can and at the end of the test you can mark your own work.\n Jonny had a packet of 160 sweets at his party and there were 30 people there.\n Everyone wanted 5 sweets except for 6 girls and 3 boys. If everyone who wanted\n sweets got 7. How many would jonny get?\nAnswer: "; cin>> answers; cin.ignore(); if ( answers == 13 ){ cout<<"CORRECT!"; cin.get(); } else if ( answers != 13 ) cout<<"INCORRECT!"; cin.get(); } // closing bracket!! else if ( calc == 7 ) { // bracket!! cout<<"\n#EXTRAS#\n 1.Symbols\n 2.Remember the number\n#"; cin>> ext; cin.ignore(); if ( ext == 1 ){ cout<<"Type in two numbers to be added together to make a symbol: "; cin>> x >> y; cin.ignore(); cout<<"The symbol made from "<< ( x ) <<" plus "<< ( y ) <<" is "<< addit ( x,y ) <<"\n"; cin.get(); }// closing bracket!! else if ( ext == 2 ) cout<<"\nRemember this number:"<< ( random_integer ) <<"\nType ok then press enter if you have memorised the number: "; cin>> ok; cin.ignore(); if ( ok == ok ) cout<<"\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nHow many numbers are displayed here: 846567298276578368726748563259873663789528265325873146857623875345283475289635873647566\n Answer: "; cin>> number; cin.ignore(); if ( number == 87 ){ cout<<"Correct! Please enter the number you were asked to memorise earlier: "; cin>> random; cin.ignore(); cin.get(); } if ( random == random_integer ){ cout<<"CORRECT! You have a great memory"; cin.get(); } else if ( number != 87 ) cout<<"INCORRECT!"; cin.get(); } }// closing bracket!! // closing bracket!! This is what you forgot int mult ( int x, int y ) { return x * y; } int subt ( int x, int y ) // code!! { return x - y; } int addi ( int x, int y ) // code!! { return x + y; } int divi ( int x, int y ) // code!! { return x / y; } char addit ( int x, int y ) // code!! { return x + y; }

ok so thats my code.... how would i make it go back to the start where you choose the options and you restart the whole thing when you come to a dead end?

[brethren]

why are you mixing c header files with c++?

[altunozara]

i just started learning c++ like 3 days ago dont kill me cause i used c with c++....please answer my question