Solve warnings with a magic range class.

src/Range.hpp

@@ -0,0 +1,37 @@
+#pragma once
+
+namespace fmri
+{
+    template<class T>
+    class Range
+    {
+    private:
+        T start_;
+        T end_;
+
+    public:
+        explicit Range(const T &num) : start_(0), end_(num) {};
+
+        Range(const T &start, const T &end) : start_(start), end_(end) {};
+
+        class Iter
+        {
+        private:
+            T cur_;
+
+        public:
+            explicit Iter(const T &cur) : cur_(cur)
+            {};
+
+            bool operator!=(const Iter& o) { return o.cur_ != cur_; }
+            Iter&operator++() { ++cur_; return *this; }
+
+            T &operator*() { return cur_; }
+        };
+
+        typedef Iter const_iterator;
+
+        const_iterator begin() const { return Iter(start_); }
+        const_iterator end() const { return Iter(end_); }
+    };
+}