parse big integer

src/file.rs

@@ -2,6 +2,7 @@ use rug::Integer;
 use std::fs;
 use std::io;
 use std::path::Path;
+use std::str::FromStr;
 
 pub struct AgcdInput {
     pub noise_bits: usize,
@@ -39,10 +40,20 @@ pub fn parse_file(path: &Path) -> io::Result<AgcdInput> {
 
     // Parse numbers from remaining lines
     let numbers: Vec<Integer> = lines
-        .filter(|line| !line.trim().starts_with("//") && !line.trim().is_empty()) // ignore comment and empty lines
-        .filter_map(|line| line.trim().parse::<u64>().ok())
-        .map(Integer::from)
-        .collect();
+        .filter(|line| {
+            let t = line.trim();
+            !t.starts_with("//") && !t.is_empty()
+        })
+        .map(|line| {
+            let s = line.trim();
+            Integer::from_str(s).map_err(|e| {
+                io::Error::new(
+                    io::ErrorKind::InvalidData,
+                    format!("Failed to parse integer '{}': {}", s, e),
+                )
+            })
+        })
+        .collect::<Result<_, io::Error>>()?;
 
     if numbers.len() < 2 {
         return Err(io::Error::new(

src/main.rs

@@ -34,11 +34,7 @@ fn main() -> std::io::Result<()> {
             let path = path.as_deref().unwrap_or(Path::new("./input.txt"));
             let input = parse_file(path)?;
 
-            let result = agcd(input.numbers, input.noise_bits);
-            println!(
-                "Approximate GCD with noise_bits={}: {}",
-                input.noise_bits, result
-            );
+            agcd(input.numbers, input.noise_bits);
         }
     }
     Ok(())