help using int main(int argc, char* argv[])

[johnny92]

Using the code,

int main(int argc, char* argv[])
{
   cout << 3*argv[] << endl;

and calling it from command line as
./name_of_program 5

I want it to produce 15, but it wont let me.

[cire]

#include <sstream>
#include <iostream>

int to_int(const char* s)
{
    std::istringstream is(s) ;

    int value ;
    is >> value ;
    return value ;
}

int main(int argc, const char* argv[])
{
    if ( argc == 2 )
        std::cout << 3*to_int(argv[1]) << '\n' ;
    else
        std::cout << "No argument provided.\n" ;
}