1. String Messy Details
Unsigned vs signed

2. String Literals are not Strings
Other things (const char[] )
Chars

3. Unsigned vs Signed Unsigned integer : unsigned int
Plain binary ≈ 4 billion
Signed (regular) integer : int
Two's complement = -1

4. Comparing Signed & Unsigned
Weirdness:

5. Strings & Unsigned String namespace defines a type size_type:
string::size_type
Used to specify size and locations in string
string::size_type length(); string::size_type find(string);
It is (usually) an unsigned int

6. So?
strValue.find(str) works different in these cases:

7. So?
strValue.find(str) works different in these cases:
4 billion -1

8. npos
string::npos Constant for largest possible value for string::size_type
Use to check for "not in string"
if( strVar.find(str) == string::npos ) {
//did not find str }

9. So what do I do?
Use -1
Direct comparison with function is warning

10. So what do I do? Use string::npos
Value stored as int will cause warning

11. So what do I do? Use string::npos and store as unsigned int
No warnings

12. So what do I do?
Use string::npos and store as size_type
Super correct