Add rust (#50)

* Add rust

* Add optimize flag

scripts/restore/restore-from-apt.sh

@@ -16,4 +16,5 @@ apt-get update && \
 		ruby \
 		golang \
 		openjdk-8-jdk-headless \
-		unzip
+		unzip \
+		rustc

sojj/languages.json

@@ -90,5 +90,12 @@
     "outputFile": "foo.jar",
     "execute": ["java", "-jar", "foo.jar"],
     "cpuLimit": 25
+  },
+  "rust2021": {
+    "type": "compiler",
+    "compile": ["/usr/bin/rustc", "-O", "foo.rs", "-o", "foo"],
+    "codeFile": "foo.rs",
+    "outputFile": "foo",
+    "execute": ["./foo"]
   }
 }

testdata/compile-test/1.rust2021

@@ -0,0 +1,11 @@
+use std::io;
+
+fn main() {
+    let mut line = String::new();
+    io::stdin().read_line(&mut line).expect("stdin");
+
+    let sum: i32 = line.split_whitespace()
+                       .map(|x| x.parse::<i32>().expect("integer"))
+                       .sum(); 
+    println!("{}", sum);
+}