40 lines
842 B
Rust
40 lines
842 B
Rust
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use rand::prelude::IteratorRandom;
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use std::collections::HashSet;
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struct RandomizedSet {
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nums: HashSet<i32>,
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}
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impl RandomizedSet {
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fn new() -> Self {
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Self {
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nums: HashSet::new(),
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}
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}
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fn insert(&mut self, val: i32) -> bool {
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self.nums.insert(val)
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}
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fn remove(&mut self, val: i32) -> bool {
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self.nums.remove(&val)
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}
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fn get_random(&self) -> i32 {
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let mut rng = rand::thread_rng();
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*self
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.nums
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.iter()
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.choose(&mut rng)
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.expect("at least one number is in the set")
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}
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}
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/*
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* Your RandomizedSet object will be instantiated and called as such:
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* let obj = RandomizedSet::new();
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* let ret_1: bool = obj.insert(val);
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* let ret_2: bool = obj.remove(val);
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* let ret_3: i32 = obj.get_random();
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*/
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