Store int to char

[maryrose0911]

How to store int/double value in a char?

[MikeyBoy]

Do you actually mean a single char? Or do you mean a C-style string, i.e. an array of chars?

[maryrose0911]

Example input values:
0.5 is the input value for P1
1 is the input value for P2
0.3 is the input value for P3

//Sort ascending order
My Program Output:
0.3
0.5
1

What I need to output is:
P3
P1
P2

How would I do it? Thanks in advance.

[MrHutch]

Characters essentially are integers. You could easily assigned an integer value to a char, assuming they're the same size. This can get a little hazy between different compilers and system architectures.

int my_int = 12345;
char32_t my_char = my_int;

Why you'd want to is another matter.

I'd imagine the same thing would happen to a double, providing the char was big enough. Though I think anything after the decimal point would be truncated.

Again, I can't see why you'd really want to do something like this.

Edit: This may be outdated. I was typed this before the above replied appeared.

[maryrose0911]

I need to sort it in ascending order by its value however the variable of the value must be the output just like my example above.

[TwilightSpectre]

You could just store it in a double and output like that anyway? Does the same thing?

EDIT:
Also, storing in a string would give problems too, such as 10 coming before 2.

[MikeyBoy]

From the description you've given, I don't see why you need to store anything in a char. You just need to read the user input as a number, sort the numbers, and then output the numbers.

Have a look at this turorial:

http://www.cplusplus.com/doc/tutorial/basic_io/

[MrHutch]

Oh, I see what you mean now. You want to associated the value with its ID. You could usually use a std::map for that sort of associating, but it can get a little messy to sort (maps by their nature are sorted by keys, not values).

You could create a struct and keep a vector of that struct, adding the appropriate elements as they're entered.

struct Foo
{
   std::string id;
   double value;
};

std::vector<Foo> my_foos;

Alternatively, you could use a vector of pairs, like this:

#include <iostream>
#include <vector>
#include <string>
#include <sstream>
#include <algorithm>

bool myComp( std::pair<std::string, double> lhs, std::pair<std::string, double> rhs ) 
{ 
    return lhs.second < rhs.second; 
}

int main( int argc, char* argv[] )
{
    std::vector<std::pair<std::string, double>> input_map;
    unsigned int count = 1;
    double input;

    std::cout << "Enter number: (Enter 0 to stop)";

    while( std::cin >> input && input != 0 )
    {
        std::cin.ignore( 256, '\n' );
        std::cin.clear();

        std::ostringstream oss;
        oss << "P" << count;

        input_map.push_back( std::pair<std::string, double>( oss.str(), input ) );
        std::cout << "Enter next number: ";

        ++count;
    }

    std::sort( input_map.begin(), input_map.end(), myComp );

    std::cout << "Ascending order:\n";

    for( const auto &i : input_map )
        std::cout << i.first << " : " << i.second << std::endl;
}