CODEWITHSUNDEEP
c++arraysstringchar
Tillman
Tillman

Reputation: 7

2D array of chars to 1D array of strings

what is the easiest way to copy a two-dimensional array of chars into a one-dimensional array of strings in c++?

something like that:

    char inCharArray[3][255];
    string outStringArray[3];

    for (int i = 0; i < sizeof(inCharArray) / sizeof(inCharArray[i]); i++)
    {
        outStringArray[i] = inCharArray[i];
    }

Regards Tillman

Upvotes: 0

Views: 268

Answers (2)

Woodford
Woodford

Reputation: 4449

This alternative to std::transform is more readable to me:

std::copy(std::begin(inCharArray),
          std::end(inCharArray),
          std::begin(outStringArray));

// only safe if input strings are null-terminated and arrays have equal size
static_assert(std::size(inCharArray) == std::size(outStringArray),
              "arrays are not equal size");

Also consider using std::array instead of C-style arrays while you're writing C++ code.

Upvotes: 0

Guillaume Racicot
Guillaume Racicot

Reputation: 41760

Using STL algorithm is one of the best way to do it.

char inCharArray[3][255];
string outStringArray[3];

std::transform(
    std::begin(inCharrArray),
    std::end(inCharArray),
    std::begin(outStringArray),
    [](char const* c_str) -> std::string {
        return std::string{c_str};
    }
);

This is assuming the strings are ending sooner than 255.

Upvotes: 1

Related Questions