Invalid operands to binary expression

User 13770707

I have this code, which works on CodeBlocks, but when I try to run it in visual studio code, I get and error saying:

invalid operands to binary expression ('std::ostream' (aka 'basic_ostream >') and 'std::string' (aka 'basic_string, allocator >'))

this is the code:

#include
using namespace std;

class field{
public:
void Create_Area(int area){
string field[area][area];

		//assign "+ " to all rows and collums and print the area
		for(int y = 0; y < area; y++){
			for(int x = 0; x < area; x++){
				field\[y\]\[x\] = "+ ";
				cout << field\[y\]\[x\];
			}
			cout << endl;
		}
	}

};

What to do to fix this?

Lost User

You cannot create an array on the stack using values that are not known at compile time. You need to change your code to:

	void Create\_Area(int area){
		string field\[\]\[\] = new string\[area\]\[area\];

Also, I would suggest not using the class name for an array in that way. And the field variable is not available outside of the method that creates it.

User 13770707

I have changed that, but now how do I use it in this part?

				Field\[y\]\[x\] = "+ ";
                cout << Field\[y\]\[x\];

also, I don't really understand what you have done in the new string[area][area] part. Why use string instead of field?

Lost User

Member 13802912 wrote:

how do I use it in this part?

Exactly the same as before.

Lost User

Member 13802912 wrote:

how do I use it in this part?

Exactly the same as before.

Member 13802912 wrote:

the new string[area][area] part. Why use string instead of field?

Because you are trying to create an array of string objects. See new Operator (C++)[^].

Member_14862667

invalid operands to binary expression ('std::ostream' (aka 'basic_ostream') and 'void')
cout<
The above error is what im getting and my code is this.Need your help.Thanks!
#include
void Find(int arr[], int n, int sum)
{
unordered_set s;
int temp;
for (int i = 0; i < n; i++)
{
temp = sum - arr[i];
if (s.find(temp) != s.end())
cout<< arr[i]<<"+"<< temp<<" ";
s.insert(arr[i]);
}
}
int main()
{
int arr[] = {1,2,3,4,5,6,6,5,56,7,11,13} ;
int n = sizeof(arr)/sizeof(arr[0]);
int sum = 12;
cout<

Member_14862667

fatal error: invalid operands to binary expression ('std::ostream' (aka 'basic_ostream') and 'void')

this is the error i am getting.What should i do?

#include
void Find(int arr[], int n, int sum)
{
unordered_set s;
int temp;
for (int i = 0; i < n; i++)
{
temp = sum - arr[i];
if (s.find(temp) != s.end())
cout<< arr[i]<<"+"<< temp<<" ";
s.insert(arr[i]);
}
}
int main()
{
int arr[] = {1,2,3,4,5,6,6,5,56,7,11,13} ;
int n = sizeof(arr)/sizeof(arr[0]);
int sum = 12;
cout<

Lost User

You have declared:

void Find(int arr[], int n, int sum)

// and then you have:
cout<
But you cannot print something that is void, i.e something that does not exist.

Member_14862667

So what should i do Instead of void i used

int Find() {.... return 0; }

But at the end of my input extra zero is coming which i dont want. Thank you!

Lost User

Then don't return a value. Leave it as void and remove the cout call at the end of your main method. BTW in future please open a new question if you have a problem, rather than reopening a thread that is over two years old.