Add problem 1871: Jump Game VII

src/lib.rs

@@ -1392,6 +1392,7 @@ pub mod problem_1865_finding_pairs_with_a_certain_sum;
 pub mod problem_1866_number_of_ways_to_rearrange_sticks_with_k_sticks_visible;
 pub mod problem_1869_longer_contiguous_segments_of_ones_than_zeros;
 pub mod problem_1870_minimum_speed_to_arrive_on_time;
+pub mod problem_1871_jump_game_vii;
 pub mod problem_1876_substrings_of_size_three_with_distinct_characters;
 pub mod problem_1877_minimize_maximum_pair_sum_in_array;
 pub mod problem_1880_check_if_word_equals_summation_of_two_words;

src/problem_1871_jump_game_vii/mod.rs

@@ -0,0 +1,18 @@
+pub mod sliding_window;
+
+pub trait Solution {
+    fn can_reach(s: String, min_jump: i32, max_jump: i32) -> bool;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    pub fn run<S: Solution>() {
+        let test_cases = [(("011010", 2, 3), true), (("01101110", 2, 3), false)];
+
+        for ((s, min_jump, max_jump), expected) in test_cases {
+            assert_eq!(S::can_reach(s.to_string(), min_jump, max_jump), expected);
+        }
+    }
+}

src/problem_1871_jump_game_vii/sliding_window.rs

@@ -0,0 +1,49 @@
+pub struct Solution;
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+use std::cell::Cell;
+
+impl Solution {
+    pub fn can_reach(s: String, min_jump: i32, max_jump: i32) -> bool {
+        let mut s = s.into_bytes();
+        let min_jump = min_jump as u32 as usize;
+        let max_jump = max_jump as u32 as usize;
+
+        s[1..min_jump].fill(b'1');
+
+        let mut count = 0;
+
+        for &c in &s[..=max_jump - min_jump] {
+            count += u32::from(b'1' - c);
+        }
+
+        let s = Cell::from_mut(s.as_mut_slice()).as_slice_of_cells();
+
+        for ((old, new), target) in s.iter().zip(&s[max_jump - min_jump + 1..]).zip(&s[max_jump + 1..]) {
+            count = count.wrapping_add(i32::from(old.get().wrapping_sub(new.get()) as i8) as u32);
+
+            if target.get() == b'0' {
+                target.set(b'1' - u8::from(count != 0));
+            }
+        }
+
+        s.last().unwrap().get() == b'0'
+    }
+}
+
+// ------------------------------------------------------ snip ------------------------------------------------------ //
+
+impl super::Solution for Solution {
+    fn can_reach(s: String, min_jump: i32, max_jump: i32) -> bool {
+        Self::can_reach(s, min_jump, max_jump)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_solution() {
+        super::super::tests::run::<super::Solution>();
+    }
+}