diff --git a/Makefile b/Makefile
index 739887b..30dbc17 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 CXX=g++
 # CPPFLAGS=-Wall -g
 # CPPFLAGS=-Wall -g -std=c++0x
-# CPPFLAGS=-Wall -g -std=c++0x -pthread
+CPPFLAGS=-Wall -g -std=c++0x -pthread
 
 all:
 	@echo "build things individually (make loops, etc.)"
diff --git a/constexpr.cc b/constexpr.cc
index 37a32a5..7cd9451 100644
--- a/constexpr.cc
+++ b/constexpr.cc
@@ -1,7 +1,7 @@
 #include <iostream>
 using namespace std;
 
-int some_constant_func() {
+constexpr int some_constant_func() {
     return 41;
 }
 
diff --git a/init.cc b/init.cc
index cb0d3c3..f4e4d13 100644
--- a/init.cc
+++ b/init.cc
@@ -11,6 +11,7 @@ struct Point {
 
 int main() {
     string s1("first");
+    string s3 = string("again");
     int x = int(42);
     string s2 = "hello";
     int y = 42;
diff --git a/init_new.cc b/init_new.cc
index 4072134..9261829 100644
--- a/init_new.cc
+++ b/init_new.cc
@@ -13,9 +13,9 @@ const vector<string> s = {"a", "b", "c"};
 int main() {
     string s1 {"first"};
     int x {42};
-    map<string, int> singers = {
-        {"Freddie Mercury", 100},
-        {"Matt Bellamy", 100},
+    map<string, vector<int>> singers = {
+        {"Freddie Mercury", {100, 102, 103}},
+        {"Matt Bellamy", {100, 104, 105}},
     };
     return 0;
 }
diff --git a/tuple.cc b/tuple.cc
index 1254a5d..ae9dcf0 100644
--- a/tuple.cc
+++ b/tuple.cc
@@ -3,16 +3,21 @@
 
 using namespace std;
 
-// make a function that returns multiple values
+auto some_func() -> tuple<int, int> {
+    return make_tuple(4, 2);
+}
 
 int main() {
-    tuple<int, int> c = make_tuple(5, 4);
+    auto c = make_tuple(5, 4);
     cout << get<0>(c) << endl;
 
     int a = 0;
     int b = 1;
+    tie(a, b) = make_tuple(b, a);
     cout << a << endl;
     cout << b << endl;
-    // swap a, b
     // get a,b from func ...
+    tie(a, b) = some_func();
+    cout << a << endl;
+    cout << b << endl;
 }