diff --git a/src/lib/misc.c b/src/lib/misc.c
index 64e177d..f061761 100644
--- a/src/lib/misc.c
+++ b/src/lib/misc.c
@@ -17,6 +17,11 @@ double multiply_cb(int a, int b) { return a * b; }
 double subtract_cb(int a, int b) { return a - b; }
 double sum_cb(int a, int b) { return a + b; }
 
+double doMathematicalOperation(int a, int b, double (*op)(int, int))
+{
+    return op(a, b);
+}
+
 int unlink_cb(const char *fpath, UNUSED const struct stat *sb, UNUSED int typeflag, UNUSED struct FTW *ftwbuf)
 {
     int rv = remove(fpath);