Thread: lvalue required as left operand of assignment

i get this error message for each of these lines when i try to run the program. i have no idea what it means. what am i doing wrong? there is a data file elsewhere in the program, and i'm reading info from that, and one column is numbers from 0-6. each of those corresponds to a name, which is what this function is supposed to do, equate the number to the family name. here's the portion of the code that's getting error

Code:

string familyName( int familyCode )
{
int n;
inFile>>n;
switch (n)
{
case 0:
	0=Drake;
	break;
case 1:
	1=Spencer;
	break;
case 2:
	2=Morgan;
	break;
case 3:
	3=Corinthos;
	break;
case 4:
	4=Webber;
	break;
case 5:
	5=Quatermaine;
	break;
case 6:
	6=Davis;
	break;
}
}

= is not symmetric in C++. The value on the right is placed in the variable on the left. Since 0, 1, ..., 6 are not variables, but constants, the assignment cannot happen.

so i'd have to make each of the numbers variables in order for it to work? but that's not possible, is it?

bear with me here, i'm not knowledgeable at all in c++. i appreciate the help so far. so would declaring the family names as int solve the problem?

Originally Posted by joeman

bear with me here, i'm not knowledgeable at all in c++. i appreciate the help so far. so would declaring the family names as int solve the problem?

Is "Drake" a number?

ok, how do i set a number equal to the name? i need this program to read 0 from the text file and display drake. i have no idea whatsoever how to do this, i've declared them as strings and ints, i don't know what to do.

Originally Posted by joeman

ok, how do i set a number equal to the name? i need this program to read 0 from the text file and display drake. i have no idea whatsoever how to do this, i've declared them as strings and ints, i don't know what to do.

Stop to think for twenty seconds instead of just trying to type the magic word.

BIG HUGE HINT: Your number and your word are not now, and never have been, supposed to be the same variable.

When you use the = operator, it takes the value on the right, and assigns it to a variable on the left. A value can be a number, a letter, a string of text, or another variable among other things.

This statement:

Code:

	0=Drake;

Won't work because '0' is not a variable (which is causing the "lvalue required as left operand of assignment" error). Another thing to remember is that a string must be put in "quotes", so unless Drake is a variable, that would also be a problem.

Now, if I understand what you're trying to do, this should fix your problem:

Code:

string familyName( int familyCode )
{
int n;
inFile>>n;
switch (n)
{
case 0:
	cout<<"Drake";
	break;
case 1:
	cout<<"Spencer";
	break;
case 2:
	cout<<"Morgan";
	break;
case 3:
	cout<<"Corinthos";
	break;
case 4:
	cout<<"Webber";
	break;
case 5:
	cout<<"Quatermaine";
	break;
case 6:
	cout<<"Davis";
	break;
}
}

I'm new to coding myself, so lemme know if I got something wrong, but this should help.

oh christ, cout<<... why on earth did i not think of that. thank you much, kind sir. thanks to everyone else as well. it's been a long day , ha

I'm glad I could help.