"equal to" versus "not equal to" operators in an if-else statement
<p>When writing if-else statements in C, is there a reason why one would preferentially use the operator "equal to" over "not equal to", when both can produce the same outcome?</p>

<p>The code below provides context. Whereby, if the argument count is equal to 2, a string will be retrieved from the user. However, if any other value of arguments is obtained, an error message will appear.</p>

<pre><code>int main(int argc, string argv[])
{
    string msg;

    if (argc == 2) 
    {
        msg = GetString();
    }
    else
    {
        printf("ERROR: Please only enter a single key! \n");
        return 1;
    }
</code></pre>

<p>However, I can achieve the exact same outcome as the above by changing the condition of the if-else loop to being "not equals to", and flipping the associated actions. See below:</p>

<pre><code>int main(int argc, string argv[])
{
    string msg;

    if (argc != 2) 
    {
        printf("ERROR: Please only enter a single key! \n");
        return 1;
    }
    else
    {
        msg = GetString();
    }
</code></pre>

<p>Anyways, as both produce the same outcome, should one be used preferentially over the other? </p>