One-liner to create a dictionary with one entry

I have a method which takes a Dictionary<int, int> as a parameter

public void CoolStuff(Dictionary<int, int> job)

I want to call that method with one dictionary entry, such as

int a = 5;
int b = 6;
var param = new Dictionary<int, int>();
param.Add(a, b);
CoolStuff(param);

How can I do it in one line?

This is it, if you do not need the a and b variables:

var param = new Dictionary<int, int> { { 5, 6 } };

or even

CoolStuff(new Dictionary<int, int> { { 5, 6 } });

Please, read How to: Initialize a Dictionary with a Collection Initializer (C# Programming Guide)

var param = new Dictionary<int, int>() { { 5, 6 } };