solution for day 6

2020/day_6/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "day_6"
+version = "0.1.0"
+authors = ["Ray Slakinski <ray.slakinski@gmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+counter = "0.5.2"

2020/day_6/src/main.rs

@@ -0,0 +1,42 @@
+use counter::Counter;
+use std::{collections::HashMap, println};
+fn main() {
+    let contents = std::fs::read_to_string("input").unwrap();
+    let mut groups = Vec::new();
+    let mut group = Vec::new();
+    let mut total_count = 0;
+
+    for line in contents.lines() {
+        if line.len() > 0 {
+            group.push(line.to_string());
+        } else {
+            groups.push(group.to_vec());
+            group.clear();
+        }
+    }
+    for g in &groups {
+        let voters = g.len();
+        let mut all_votes: Vec<HashMap<char, usize>> = Vec::new();
+        for v in g {
+            let counts = v.chars().collect::<Counter<_>>();
+            all_votes.push(counts.into_map());
+        }
+        println!("{:?}", all_votes);
+        let mut vote_count = 0;
+        for c in b'a'..=b'z' {
+            for v in &all_votes {
+                let l = c as char;
+                // println!("{:?}", v[&l]);
+                if v.contains_key(&l) {
+                    vote_count += 1;
+                }
+            }
+            if vote_count == voters {
+                total_count += 1;
+            }
+            vote_count = 0
+        }
+        all_votes.clear()
+    }
+    println!("Total unique people voted {}", total_count);
+}

2020/day_6/test

@@ -0,0 +1,16 @@
+abc
+
+a
+b
+c
+
+ab
+ac
+
+a
+a
+a
+a
+
+b
+