Added tutorial 20

README.md

@@ -22,6 +22,7 @@ The companion to the Youtube tutorials
 - [Learning Solidity : Tutorial 17 Polymorphism](https://www.youtube.com/watch?v=l_E5F5qnbtk)
 - [Learning Solidity : Tutorial 18 Randomness and Gambling](https://www.youtube.com/watch?v=3wY5PRliphE)
 - [Learning Solidity : Tutorial 19 Nested Arrays and Storage](https://www.youtube.com/watch?v=zkNHRJEuYQg)
+- [Learning Solidity : Tutorial 20 Parameter Mapping and Multiple Return Values](https://www.youtube.com/watch?v=v3aoiTh-UVQ)
 
 ### Support
 

tutorial-20/Assignments.sol

@@ -0,0 +1,23 @@
+pragma solidity ^0.4.0;
+
+contract Assignments {
+    function returnFirstValue(uint a, uint b) returns (uint) {
+        return a;
+    }
+
+    function caller() public returns (uint) {
+        return returnFirstValue({b:4, a:8});
+    }
+
+    function returnAllValues(uint a, uint b, uint c) returns (uint, uint, uint) {
+        return (a,b,c);
+    }
+
+    function callerAll() public returns (uint, uint, uint) {
+        var(x,y,z) = returnAllValues(4,5,6);
+        (x,y) = (y,x);
+        (x,) = returnAllValues(5,10,15);
+        (,z) = returnAllValues(10,20,30);
+        return (x,y,z);
+    }
+}