finished day 1

src/bin/1.rs

@@ -40,8 +40,30 @@ use std::{fs::{File}, io};
 use std::collections::HashSet;
 use std::io::{BufRead, BufReader};
 
+fn find_triple(target: i32, list: &Vec<i32>, set: &HashSet<i32>) -> i32 {
+    for i in list {
+        let product = find_pair(target - i, list, set);
+        if product > 0 {
+            return product * i;
+        }
+    }
+    0
+}
+
+fn find_pair(target: i32, list: &Vec<i32>, set: &HashSet<i32>) -> i32 {
+    for i in list {
+        if i > &target {
+            break
+        }
+        let val = target - i;
+        if set.contains(&val) {
+            return i * val;
+        }
+    }
+    0
+}
+
 fn main() -> io::Result<()> {
-    //let contents = fs::read_to_string("1.input").expect("Couldn't read \"1.input\"");
     let file = File::open("1.input")?;
     let reader = BufReader::new(file);
 
@@ -53,5 +75,10 @@ fn main() -> io::Result<()> {
         list.push(value);
         set.insert(value);
     }
+
+    list.sort();
+
+    println!("Pair is {}", find_pair(2020, &list, &set));
+    println!("Triple is {}", find_triple(2020, &list, &set));
     Ok(())
 }