rust day 7 part 1

rust/day7/Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "day7"
+version = "0.1.0"

rust/day7/Cargo.toml

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+[package]
+name = "day7"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

rust/day7/src/main.rs

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+use std::fs;
+use std::io::BufRead;
+
+static PATH: &'static str = "../../inputs/input-day7";
+
+fn remove_whitespace(s: &str) -> String {
+    return s.split_whitespace().collect();
+}
+
+fn load_file() -> Result<Vec<i64>, std::io::Error> {
+    let file = fs::File::open(PATH)?;
+    let reader = std::io::BufReader::new(file);
+    let res: Vec<i64> = reader.split(b',').map(|p| {
+        let p = p.unwrap();
+        let v = String::from_utf8_lossy(&p);
+        return remove_whitespace(&v).parse::<i64>().unwrap();
+    }).collect();
+    return Ok(res);
+}
+
+fn calc_fuel_for_pos(v: &Vec<i64>, pos: i64) -> i64 {
+    let mut total = 0;
+
+    for x in v {
+        if x > &pos {
+            total += x - pos;
+        } else if x < &pos {
+            total += pos - x;
+        }
+    }
+
+    return total;
+}
+
+fn get_max(v: &Vec<i64>) -> i64 {
+    let mut max = 0;
+    for i in v {
+        if i > &max {
+            max = *i;
+        }
+    }
+    return max
+}
+
+fn main() {
+    let pos = load_file().unwrap();
+    let max = get_max(&pos);
+
+    let mut lowest = 0;
+    let mut lastpos = 0;
+
+    for i in 0..max {
+        let fuel = calc_fuel_for_pos(&pos, i);
+        if i == 0 {
+            lowest = fuel;
+        }
+        if fuel < lowest {
+            lowest = fuel;
+            lastpos = i;
+        }
+    }
+
+    println!("lowest consumption is pos {} with {} fuel", lastpos, lowest);
+}