Pseudocode below shows what I am trying to achieve. I am new to C++ and pointers, as you can guess from this question. So, I don't know what to pass to function [1], what to get from parameter [2], and what to use to make comparison [3].
Please do not ask why I am passing a pointer instead of the value itself, the function only accepts pointers for this task.
I need some help.
main {
string someString = ..
function(pointer of the string above [1]*);
}
function (parameter[2]*) {
if (parameter[3]* == "Hello World") {
print("okay");
}
}
It depends on what language you are using.
In C++ the program can look like
#include <iostream>
#include <string>
void check( const std::string &s )
{
if ( s == "Hello World" )
{
std::cout << "okay" << '\n';;
}
}
int main()
{
std::string someString = "Hello World";
check( someString );
}
In C a corresponding program can look like
#include <stdio.h>
#include <string.h>
void check( const char *s )
{
if ( strcmp( s, "Hello World" ) == 0 )
{
puts( "okay" );
}
}
int main( void )
{
char someString[] = "Hello World";
check( someString );
}
A similar program using a character array is also can be written in C++.
Instead of the declaration of the array
char someString[] = "Hello World";
you could declare a pointer to the string literal like
const char *someString = "Hello World";
You have a couple of options here:
By passing the variable by reference, you will change the main string, unless your function accepts the pointer as constant. You can do that by doing the following:
main {
string someString = ...;
// Notice here we are passing the variable by reference
// We are passing the variable's address to the function
function(&somestring);
}
And with the second option, you can do the following:
main {
string* someString = new string(...);
// Pass it normally, as it will be accepted
function(someString);
}
And in the function itself you can use that value as it follows:
function(paramString) {
if(*paramString == "Hello World") {
do something..
}
}
Please read some more information about function parameters and arguments, and about pointers itself.
The links below will give you a head start.
https://www.w3schools.com/cpp/cpp_function_param.asp https://www.w3schools.com/cpp/cpp_pointers.asp
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