ownership, references

ch03_practice/src/main.rs

@@ -0,0 +1,40 @@
+fn f_to_c(f: f64) -> f64 {
+    (f - 32.0) * (5.0 / 9.0)
+}
+
+fn c_to_f(c: f64) -> f64 {
+    c * (9.0 / 5.0) + 32.0
+}
+
+fn main() {
+
+    // f to c / c to f
+    let f1 = 0.0;
+    let f2 = 32.0;
+    let f3 = 80.0;
+    let f4 = 212.0;
+    let c1 = f_to_c(f1);
+    let c2 = f_to_c(f2);
+    let c3 = f_to_c(f3);
+    let c4 = f_to_c(f4);
+
+    println!("{f1}f {c1}c");
+    println!("{f2}f {c2}c");
+    println!("{f3}f {c3}c");
+    println!("{f4}f {c4}c");
+
+    let f5 = c_to_f(100.0);
+    println!("100c = {f5}f");
+    // fib
+    //
+    let mut x1 = 0;
+    let mut x2 = 1;
+    let mut temp = 0;
+    while x1 < 2000 {
+        println!("x: {x1}");
+        temp = x2;
+        x2 = x1 + x2;
+        x1 = temp;
+    }
+}
+