remove unused day1 code

2020/day_1/src/main.rs

@@ -1,7 +1,4 @@
 fn main() {
-    // let mut file = std::fs::File::open("input1").unwrap();
-    // let mut contents = String::new();
-    // file.read_to_string(&mut contents).unwrap();
     let mut v: Vec<i32> = Vec::new();
     let contents = std::fs::read_to_string("input1").unwrap();
     for s in contents.lines() {