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problems/0704.二分查找.md

@@ -484,6 +484,7 @@ func search(nums: [Int], target: Int) -> Int {
 （版本一）左闭右开区间
 
 ```rust
+use std::cmp::Ordering;
 impl Solution {
     pub fn search(nums: Vec<i32>, target: i32) -> i32 {
         let (mut left, mut right) = (0, nums.len());
@@ -503,6 +504,7 @@ impl Solution {
 //（版本二）左闭右闭区间
 
 ```rust
+use std::cmp::Ordering;
 impl Solution {
     pub fn search(nums: Vec<i32>, target: i32) -> i32 {
         let (mut left, mut right) = (0, nums.len());