From 976a1086ee8c30398582df1727ffb27679b2c2d7 Mon Sep 17 00:00:00 2001
From: YangNianYi <y790174683@163.com>
Date: Sat, 9 Sep 2023 15:55:35 +0800
Subject: [PATCH] feat: u32 from_be_bytes (#765)

---
 candle-datasets/src/vision/mnist.rs | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/candle-datasets/src/vision/mnist.rs b/candle-datasets/src/vision/mnist.rs
index 30b0d01f..7a8240cf 100644
--- a/candle-datasets/src/vision/mnist.rs
+++ b/candle-datasets/src/vision/mnist.rs
@@ -9,12 +9,9 @@ use std::fs::File;
 use std::io::{self, BufReader, Read};
 
 fn read_u32<T: Read>(reader: &mut T) -> Result<u32> {
-    let mut b = vec![0u8; 4];
+    let mut b = [0u8; 4];
     reader.read_exact(&mut b)?;
-    let (result, _) = b.iter().rev().fold((0u64, 1u64), |(s, basis), &x| {
-        (s + basis * u64::from(x), basis * 256)
-    });
-    Ok(result as u32)
+    Ok(u32::from_be_bytes(b))
 }
 
 fn check_magic_number<T: Read>(reader: &mut T, expected: u32) -> Result<()> {