1

Author: Ainevsia

notes/src/day6/lc202.md

@@ -40,4 +40,27 @@ impl Solution {
 ```
 ## 学习感想
 
-一下子不知道怎么做，但是把false的例子弄明白就知道了
+一下子不知道怎么做，但是把false的例子弄明白就知道了
+
+
+```rust
+# struct Solution {}
+
+impl Solution {
+    pub fn is_happy(mut n: i32) -> bool {
+        use std::collections::HashSet;
+        let mut set: HashSet<i32> = HashSet::from([n]);
+        loop {
+            let mut new = 0i32;
+            while n != 0i32 {
+                new += (n % 10i32).pow(2u32);
+                n /= 10i32;
+            }
+            if new == 1i32 { break true }
+            if set.contains(&new) { break false }
+            set.insert(new);
+            n = new;
+        }
+    }
+}
+```

notes/src/day6/lc349.md

@@ -33,9 +33,10 @@ impl Solution {
 impl Solution {
     pub fn intersection(nums1: Vec<i32>, nums2: Vec<i32>) -> Vec<i32> {
         use std::collections::HashSet;
-        let set1: HashSet<i32> = HashSet::from_iter(nums1.into_iter());
-        let set2: HashSet<i32> = HashSet::from_iter(nums2.into_iter());
-        set1.intersection(&set2).map(|&x| x).collect()
+        let set1: HashSet<i32> = HashSet::from_iter(nums1);
+        let set2: HashSet<i32> = HashSet::from_iter(nums2);
+        // set1.intersection(&set2).map(|&x| x).collect()
+        set1.intersection(&set2).copied().collect()
     }
 }