diff --git a/umn-kauffman/.gitignore b/umn-kauffman/.gitignore
new file mode 100644
index 0000000..5683457
--- /dev/null
+++ b/umn-kauffman/.gitignore
@@ -0,0 +1 @@
+*.s
diff --git a/umn-kauffman/exchange.c b/umn-kauffman/exchange.c
new file mode 100644
index 0000000..dbe4b37
--- /dev/null
+++ b/umn-kauffman/exchange.c
@@ -0,0 +1,7 @@
+long
+exchange(long *xp, long y)
+{
+  long x = *xp;
+  *xp = y;
+  return x;
+}
diff --git a/umn-kauffman/goop.c b/umn-kauffman/goop.c
new file mode 100644
index 0000000..b745c6b
--- /dev/null
+++ b/umn-kauffman/goop.c
@@ -0,0 +1,11 @@
+#include <stdio.h>
+
+int
+main(int argc, char *argv[])
+{
+  for (int i = argc; i > -1; i--) {
+    printf("(%d): %s\n", i, argv[i]);
+  }
+
+  return 0;
+}
diff --git a/umn-kauffman/mstore.c b/umn-kauffman/mstore.c
new file mode 100644
index 0000000..071d2f8
--- /dev/null
+++ b/umn-kauffman/mstore.c
@@ -0,0 +1,9 @@
+long
+mult2(long a, long b);
+
+void
+multstore(long x, long y, long *dest)
+{
+  long t = mult2(x, y);
+  *dest = t;
+}