C++ Can't subtract two strings
Solution 1
You should use std::string::substr
. Subtracting strings like that is invalid.
firstName = employeeName.substr(0, employeeName.find(" "));
The first parameter is the starting index of the substring you want to extract and the second parameter is the length of the substring.
Solution 2
There is no "minus" (-) operator for std::string. You have to use std::string::substr or std::string::erase
If you really want to use - operator, you can overload it.
Solution 3
How would you define a minus operator for a string? Would you subtract from the beginning? Or the end?
Moreover, what is "cat" - "dog"
? This operator wouldn't make sense.
Instead, you might want to use string indices, i.e. employeeName[i]
, and copy characters individually, or use std::string::substr
or std::string::erase
, as others have suggested.
I would find substr()
the easiest, due to its ability to remove sections of string (in this case, the first and last name).
Haris Irshad
Updated on October 18, 2020Comments
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Haris Irshad over 3 years
I want to subtract two strings in this code, but it won't let me do it and gives an operator - error. This code basically tries to separate a full input name into two outputs: first and last names. Please Help! Thank you!
#include <iostream> #include <cstdlib> #include <string> using namespace std; string employeeName, firstName, lastName; int pos1, difference; int main() { cout << "Enter your full name: " << endl; getline(cin, employeeName); pos1 = employeeName.find(" "); difference = pos1 - 0; lastName = employeeName.erase(0,difference); firstName = employeeName - lastName; cout << lastName << firstName << endl; system("pause"); return 0; }