some more problems

divide-two-integers/sol.rs

@@ -0,0 +1,31 @@
+// Assume shift operators are allowed
+impl Solution {
+    #[inline]
+    pub fn negative(n: i32) -> i32 {
+        if n.is_positive() {
+            return !(n - 1);
+        }
+        n
+    }
+    pub fn divide(dividend: i32, divisor: i32) -> i32 {
+        let positive = dividend ^ divisor >= 0;
+        let negative_divisor = Solution::negative(divisor);
+        let negative_answer = (0..negative_divisor.leading_ones()) // Preform all arithmetic in negative because of larger available range of numbers
+            .rev() // Reverse to get most extreme subdivisor first
+            .map(|n| negative_divisor << n) // Generate subdivisors
+            .fold((0, Solution::negative(dividend)), |(quotient, carry), subdivisor| {
+                if subdivisor >= carry {
+                    return ((quotient << 1) - 1, carry - subdivisor);
+                }
+                return (quotient << 1, carry);
+            }).0;
+        if positive {
+            let answer = !negative_answer;
+            if answer != std::i32::MAX {
+                return answer + 1;
+            }
+            return answer;
+        }
+        negative_answer
+    }
+}