solutions: 42

src/bin/coded_triangle_numbers.rs

@@ -0,0 +1,30 @@
+use std::fs;
+
+fn main() {
+    let alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+    let mut characters = vec![];
+
+    for c in alphabet.chars() {
+        characters.push(c);
+    }
+    
+    let contents = fs::read_to_string("assets/input")
+        .expect("Could not read the input file").replace("\"\n", "");
+    let words = contents.split("\",\"").collect::<Vec<&str>>();
+
+    let mut triangles = 0;
+    for word in &words {
+        let mut total_index = 0;
+        for character in word.chars() {
+            let index = characters.iter().position(|c| *c == character).unwrap()+1;
+            total_index += index;
+        }
+
+        let position: f64 = ((-1 as f64)+(((1+8*total_index) as f64).sqrt() as f64))/2.;
+        if position.fract() == 0. {
+            triangles += 1;
+        }
+    }
+
+    println!("{}", triangles);
+}