Create 347-top-k-frequent-elements.rs

Author: memorycancel

347-top-k-frequent-elements.rs

@@ -0,0 +1,18 @@
+pub fn top_k_frequent(nums: Vec<i32>, k: i32) -> Vec<i32> {
+    use std::collections::HashMap;
+    let mut mmp = HashMap::new();
+    for num in nums {
+        let count = mmp.entry(num).or_insert(0);
+        *count += 1;
+    }
+    let mut mv = mmp.iter().collect::<Vec<_>>();
+    mv.sort_by(|a, b|b.1.cmp(&a.1));
+    mv[0..k as usize].into_iter().map(|e|*e.0).collect()
+}
+
+fn main() {
+    let nums = vec![1, 1, 1, 2, 2, 3];
+    let k = 2;
+    println!("{:?}", top_k_frequent(nums, k));
+    println!("{:?}", top_k_frequent(vec![4,1,-1,2,-1,2,3], 2));
+}