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"lvalue required as left operand of assignment " error

The following code produces a "lvalue required as left operand of assignment"

if( c >= 'A' && c <= 'Z'  || c = " " || c = ",") {

I assume I'm writing this wrong, what is wrong? and how 开发者_运维知识库would I write it correctly?


You should use single quotes for chars and do double equals for equality (otherwise it changes the value of c)

if( c >= 'A' && c <= 'Z'  || c == ' ' || c == ',') {

Furthermore, you might consider something like this to make your boolean logic more clear:

if( (c >= 'A' && c <= 'Z')  || c == ' ' || c == ',') {

Although your boolean logic structure works equivalently (&& takes precedence over ||), things like this might trip you up in the future.


equality is ==, = is assignment. You want to use ==. Also "" is a char*, single quotes do a character.

Also, adding some parens to your condition would make your code much easier to read. Like so

 ((x == 'c' && y == 'b') || (z == ',') || (z == ' '))


= is the assigning operator, not the comparing operator. You are looking for ==.


Personally, I prefer the minimalist style:

((x == 'c' && y == 'b') || (z == ',') || (z == ' '))

(  x == 'c'  &&  y == 'b'   ||   z == ','   ||   z == ' '  )

or

(  x == 'c'  &&  y == 'b'  ?  z == ','  :  z == ' '  )

against

( x == 'c' && y == 'b' ? z == ',' : z == ' ')
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