015 ok

016/main.rs

@@ -0,0 +1,56 @@
+struct Num { rdigits: Vec<u8> }
+
+impl Num {
+    pub fn from(s: &String) -> Num {
+        let rd: Vec<u8> = s.chars().rev()
+                    .map(|c| String::from(c).parse::<u8>().unwrap())
+                    .collect();
+        Num { rdigits: rd }
+    }
+    pub fn add(&self, n: &Num) -> Num {
+        let mut xs = self.rdigits.clone();
+        let mut ys = n.rdigits.clone();
+        let mut rs: Vec<u8> = Vec::new();
+
+        while xs.len() < ys.len() { xs.push(0); }
+        while ys.len() < xs.len() { ys.push(0); }
+
+        let mut rm = 0u8;
+        for (a, b) in xs.iter().zip(ys.iter()) {
+            if a + b + rm > 9 {
+                rs.push((a + b + rm) - 10);
+                rm = 1u8;
+            } else {
+                rs.push(a + b + rm);
+                rm = 0u8;
+            }
+        }
+        if rm > 0 { rs.push(1u8); }
+
+        Num { rdigits: rs }
+    }
+    pub fn len(&self) -> usize { self.rdigits.len() }
+    pub fn print(&self) {
+        for c in self.rdigits.iter().rev() { print!("{}", c); };
+        println!("");
+    }
+}
+
+
+fn main() {
+    let mut fa = Num::from(&String::from("1"));
+    let mut fb = Num::from(&String::from("1"));
+    let mut i = 2;
+    let l = 1000usize;
+
+    while fb.len() < l {
+        let fc = fa.add(&fb);
+        fa = fb;
+        fb = fc;
+        i += 1;
+    }
+    fb.print();
+    println!("-----------");
+    println!("[{}]", i);
+
+}