68 lines
1.2 KiB
Rust
68 lines
1.2 KiB
Rust
/**
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* [191] Number of 1 Bits
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*/
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pub struct Solution {}
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// submission codes start here
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impl Solution {
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pub fn hamming_weight(n: i32) -> i32 {
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static ARRAY: [i32; 31] = [
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1 << 30,
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1 << 29,
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1 << 28,
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1 << 27,
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1 << 26,
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1 << 25,
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1 << 24,
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1 << 23,
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1 << 22,
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1 << 21,
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1 << 20,
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1 << 19,
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1 << 18,
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1 << 17,
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1 << 16,
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1 << 15,
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1 << 14,
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1 << 13,
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1 << 12,
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1 << 11,
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1 << 10,
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1 << 9,
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1 << 8,
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1 << 7,
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1 << 6,
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1 << 5,
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1 << 4,
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1 << 3,
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1 << 2,
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1 << 1,
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1,
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];
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let mut result = 0;
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for i in 0..31 {
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if n & ARRAY[i] == ARRAY[i] {
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result += 1;
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}
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}
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result
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}
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}
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// submission codes end
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#[cfg(test)]
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mod tests {
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use super::*;
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#[test]
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fn test_191() {
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assert_eq!(3, Solution::hamming_weight(11));
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assert_eq!(1, Solution::hamming_weight(128));
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}
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}
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