Initial commit.

functions/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "functions"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

functions/src/main.rs

@@ -0,0 +1,9 @@
+fn main() {
+    let x = plus_one(-1);
+
+    println! ("x 的值为：{}", x);
+}
+
+fn plus_one(x: i32) -> i32 {
+    x + 1
+}