Merge pull request neetcode-gh#1926 from AkifhanIlgaz/0895

Create: 0895-maximum-frequency-stack.rs / .ts / .js

javascript/0895-maximum-frequency-stack.js

@@ -0,0 +1,29 @@
+class FreqStack {
+ constructor() {
+ this.cnt = {};
+ this.maxCnt = 0;
+ this.stacks = {};
+ }
+
+ push(val) {
+ let valCnt = 1 + (this.cnt[val] || 0);
+ this.cnt[val] = valCnt;
+
+ if (valCnt > this.maxCnt) {
+ this.maxCnt = valCnt;
+ this.stacks[valCnt] = [];
+ }
+ this.stacks[valCnt].push(val);
+ }
+
+ pop() {
+ let res = this.stacks[this.maxCnt].pop();
+ this.cnt[res] -= 1;
+
+ if (this.stacks[this.maxCnt].length == 0) {
+ this.maxCnt -= 1;
+ }
+
+ return res;
+ }
+}

rust/0895-maximum-frequency-stack.rs

@@ -0,0 +1,35 @@
+use std::collections::HashMap;
+struct FreqStack {
+ count: HashMap<i32, i32>,
+ max_count: i32,
+ stacks: HashMap<i32, Vec<i32>>,
+}
+
+impl FreqStack {
+ fn new() -> Self {
+ Self {
+ count: HashMap::new(),
+ max_count: 0,
+ stacks: HashMap::new(),
+ }
+ }
+
+ fn push(&mut self, val: i32) {
+ let val_count = 1 + *self.count.get(&val).or(Some(&0)).unwrap();
+ self.count.insert(val, val_count);
+ if val_count > self.max_count {
+ self.max_count = val_count;
+ self.stacks.insert(val_count, vec![]);
+ }
+ self.stacks.get_mut(&val_count).unwrap().push(val);
+ }
+
+ fn pop(&mut self) -> i32 {
+ let res = self.stacks.get_mut(&self.max_count).unwrap().pop().unwrap();
+ *self.count.get_mut(&res).unwrap() -= 1;
+ if self.stacks.get(&self.max_count).unwrap().is_empty() {
+ self.max_count -= 1;
+ }
+ res
+ }
+}

typescript/0895-maximum-frequency-stack.ts

@@ -0,0 +1,32 @@
+class FreqStack {
+ cnt: Map<number, number>;
+ maxCnt: number;
+ stacks: Map<number, number[]>;
+ constructor() {
+ this.cnt = new Map();
+ this.maxCnt = 0;
+ this.stacks = new Map();
+ }
+
+ push(val: number): void {
+ let valCnt: number = 1 + (this.cnt.get(val) || 0);
+ this.cnt.set(val, valCnt);
+
+ if (valCnt > this.maxCnt) {
+ this.maxCnt = valCnt;
+ this.stacks.set(valCnt, []);
+ }
+ this.stacks.get(valCnt)?.push(val);
+ }
+
+ pop(): number {
+ let res: number = this.stacks.get(this.maxCnt)?.pop()!;
+ this.cnt.set(res, this.cnt.get(res)! - 1);
+
+ if (this.stacks.get(this.maxCnt)?.length == 0) {
+ this.maxCnt -= 1;
+ }
+
+ return res;
+ }
+}