057 begin

057/main.rs

@@ -0,0 +1,33 @@
+struct D {
+    a: u32,
+    b: u32
+}
+
+impl D {
+    pub fn from(a: u32, b: u32) -> D {
+        D { a: a, b: b }
+    }
+    pub fn print(&self) {
+        println!("{}/{}", self.a, self.b);
+    }
+    pub fn add_n(&self, n: u32) -> D {
+        let aa = self.b;
+        return D::from(aa + self.a, self.b);
+    }
+    pub fn iter(&self) -> D {
+        let mut res = self.add_n(1);
+        let dd = D::from(res.b, res.a);
+        return dd.add_n(1);
+    }
+}
+
+
+fn main() {
+    let mut d = D::from(1, 2);
+    d = d.add_n(1);
+    d.print();
+    for n in 0..100 {
+        d = d.iter();
+        d.print();
+    }
+}