Initialize values in an array of strings c++

Question

Hello i'm from Indonesia. and i'm verry beginner on C++ programming. I have some problem when i learn about string on C++ . First i declared array of char and i want to initialize a value separately in different command. After i initialize the value my compiler say "Invalid Argument".

    #include <iostream>

    using namespace std;

    int main() {

    char Name[5];

    Name = "Luke";

    cout<<"Character 0 :"<<Name[0]<<endl;
    cout<<"Character 1 :"<<Name[1]<<endl;
    cout<<"Character 2 :"<<Name[2]<<endl;
    cout<<"Character 3 :"<<Name[3]<<endl;
    cout<<"Character 4 :"<<Name[4]<<endl;

    return 0;

    }

sorry if my english is bad :(

Possible duplicate of [Assigning value to char array](https://stackoverflow.com/questions/14915924/assigning-value-to-char-array) — E. Villiger, Nov 19 '17 at 13:09
Because, you can't assign to arrays (you can initialize them, though). Consider reading a [good C++ book](https://stackoverflow.com/questions/388242/the-definitive-c-book-guide-and-list). — Algirdas Preidžius, Nov 19 '17 at 13:10

score 2 · Answer 1 · edited Jun 20 '20 at 09:12

2

A character array(including a C string) can not have a new value assigned to it after it is declared.

The C++compiler interprets these assignment statements as attempts to change the address stored in the array name, not as attempts to change the contents of the array.

However you can use

char name[] = "Luke";

edited Jun 20 '20 at 09:12

Community

1
1

answered Nov 19 '17 at 13:14

Digvijaysinh Gohil

1,367
2
15
30

score 0 · Answer 2 · answered Nov 19 '17 at 13:23

A char[] can't be assigned with a string with the = operator, except for on its initialization. That's why char Name[5]; Name = "Luke"; is invalid while char Name[5] = "Luke"; is.

Assigning strings to char[] can be done with strcpy() / memcpy()-like functions.

So you have two ways of action (assuming you want to work with char[]):

char Name[5] = "Luke";
char Name[5]; strcpy(Name, "Luke"); /* don't forget to #include <string.h>*/

score 0 · Answer 3 · answered Nov 19 '17 at 13:33

Just for sake of education (since the other answers are on-point to answer the question), here's how I would have written your code to do nearly the same thing.

The changes demonstrate:

used a more appropriate container (a string instead of a char[])
checked for access overruns
moved "one unit of work" into its own subroutine

Code was compiled as C++17 with /usr/bin/clang++ -Weverything -Wno-c++98-compat --std=c++1z:

#include <cstddef>
#include <iostream>
#include <string>

using std::cout;
using std::endl;
using std::string;

void PrintCharAtPos(string const& s, string::size_type pos);

int main() {
  auto Name = string{"Luke"};

  PrintCharAtPos(Name, 0);
  PrintCharAtPos(Name, 1);
  PrintCharAtPos(Name, 2);
  PrintCharAtPos(Name, 3);
  PrintCharAtPos(Name, 4);

  return EXIT_SUCCESS;
}

void PrintCharAtPos(string const& s, string::size_type pos) {
  if (pos < s.length())
    cout << "Character " << pos << " : " << s[pos] << endl;
  else
    cout << "Character " << pos << " : (out of bounds)" << endl;
}

Initialize values in an array of strings c++

3 Answers3

However you can use