diff --git a/DS1-2015/E3.in b/DS1-2015/E3.in
new file mode 100644
index 0000000..729832b
--- /dev/null
+++ b/DS1-2015/E3.in
@@ -0,0 +1,8 @@
+-3
+4
+6
+-8
+1
+-1
+-1
+1
diff --git a/DS1-2015/E4-1.in b/DS1-2015/E4-1.in
new file mode 100644
index 0000000..aa2c9fd
--- /dev/null
+++ b/DS1-2015/E4-1.in
@@ -0,0 +1,20 @@
+5
+-1
+1
+-2
+4
+1
+-3
+-1
+1
+-1
+-1
+1
+-2
+4
+-1
+5
+-3
+9
+2
+
diff --git a/DS1-2015/E4-2.in b/DS1-2015/E4-2.in
new file mode 100644
index 0000000..2cfb1d2
--- /dev/null
+++ b/DS1-2015/E4-2.in
@@ -0,0 +1,19 @@
+5
+-2
+-1
+4
+-2
+1
+-3
+-1
+1
+-1
+-1
+1
+-2
+2
+-1
+7
+-1
+5
+-4