Added Maximum Distance to Closest Person

Author: ryanoneill

src/lib.rs

@@ -565,6 +565,8 @@ pub mod keys_and_rooms; // 841 ✓
 
 pub mod backspace_string_compare; // 844 ✓
 
+pub mod maximum_distance_to_closest_person; // 849 ✓
+
 pub mod peak_index_in_a_mountain_array; // 852 ✓
 pub mod car_fleet; // 853 ✓
 

src/maximum_distance_to_closest_person.rs

@@ -0,0 +1,93 @@
+/// You are given an array representing a row of `seats` where `seats[i] = 1` represents a person
+/// sitting in the `ith` seat, and `seats[i] == 0` represents the `ith` seat is empty (0-indexed).
+///
+/// There is at least one empty seat, and at least one person sitting.
+///
+/// Alex wants to sit in the seat such that the distance between him and the closest person to him
+/// is maximized.
+///
+/// Return that maximum distance to the closest person.
+struct Solution;
+
+impl Solution {
+
+    pub fn max_dist_to_closest(seats: Vec<i32>) -> i32 {
+        let n = seats.len();
+
+        let mut result = 0;
+        let mut last_filled;
+
+        let mut i = 0;
+        loop {
+            if seats[i] == 1 {
+                last_filled = i;
+                if i > 0 {
+                    result = i;
+                }
+                break;
+            }
+            i += 1;
+        }
+
+        for j in i..n {
+            if seats[j] == 1 {
+                let diff = (j - last_filled) / 2;
+                if diff > result {
+                    result = diff;
+                }
+                last_filled = j;
+            }
+        }
+
+        if seats[n-1] == 0 {
+            let diff = n-1 - last_filled;
+            if diff > result {
+                result = diff;
+            }
+        }
+
+        result as i32
+    }
+
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    #[test]
+    fn example_1() {
+        let seats = vec![1,0,0,0,1,0,1];
+        let result = Solution::max_dist_to_closest(seats);
+        assert_eq!(result, 2);
+    }
+
+    #[test]
+    fn example_2() {
+        let seats = vec![1,0,0,0];
+        let result = Solution::max_dist_to_closest(seats);
+        assert_eq!(result, 3);
+    }
+
+    #[test]
+    fn example_3() {
+        let seats = vec![0,1];
+        let result = Solution::max_dist_to_closest(seats);
+        assert_eq!(result, 1);
+    }
+
+    #[test]
+    fn example_4() {
+        let seats = vec![0,0,0,1,0,1,0];
+        let result = Solution::max_dist_to_closest(seats);
+        assert_eq!(result, 3);
+    }
+
+    #[test]
+    fn example_5() {
+        let seats = vec![0,1,0,0,0,0,0,0,1,0,0,1];
+        let result = Solution::max_dist_to_closest(seats);
+        assert_eq!(result, 3);
+    }
+
+}