LeetCode Daily Problem P3370 Smallest Integer With Only Set Bits

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Timeline

Timeline

2025-10-29

init

Bit manipulation

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Problem:

P3370 Smallest Integer With Only Set Bits

https://leetcode.cn/problems/smallest-number-with-all-set-bits/description/?envType=daily-question&envId=2025-10-29

Simple Bit Manipulation

struct Solution;
impl Solution {
    pub fn smallest_number(n: i32) -> i32 {
        let mut i = 1_i64;
        while i < n as i64 {
            i = (i << 1) | 1;
        }
        i as i32
    }
}
fn main() {
    println!("Hello, world!");
}