Divide Two Integers LeetCode solution in Rust

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impl Solution {
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  pub fn divide(dividend: i32, divisor: i32) -> i32 {
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    let is_neg = (dividend < 0) ^ (divisor < 0);
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    let mut p = if dividend > 0 { -dividend } else { dividend };
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    let q = if divisor > 0 { -divisor } else { divisor };
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    // res is the *negative* absolute value of the quotient, in case the quotient is i32::MIN.
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    let mut res = 0;
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    // Here is the magic: the negative divisor(aka q) can left-shift atmost q.leading_ones() - 1 bits before it overflows.
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    for shift in (0..q.leading_ones()).rev() {
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      // Don't apply "p -= (q << shift)" before overflow checking. Consider p = 0, q << shift = i32::MIN.
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      if (p <= (q << shift)) {
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        p -= q << shift;
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        res += -1 << shift; // Not "res -= 1 << shift;" which may cause overflow.
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      }
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    }
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    if is_neg {
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      res
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    } else if res == i32::MIN {
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      i32::MAX
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    } else {
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      -res
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    }
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  }
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}