20241005 finished.

src/problem/mod.rs

@@ -255,3 +255,4 @@ mod p983_minimum_cost_for_tickets;
 mod p1870_minimum_speed_to_arrive_on_time;
 mod p1928_minimum_cost_to_reach_destination_in_time;
 mod p1227_airplane_seat_assignment_probability;
+mod p2187_minimum_time_to_complete_trips;

src/problem/p2187_minimum_time_to_complete_trips.rs

@@ -0,0 +1,52 @@
+/**
+ * [2187] Minimum Time to Complete Trips
+ */
+pub struct Solution {}
+
+
+// submission codes start here
+
+impl Solution {
+    pub fn minimum_time(time: Vec<i32>, total_trips: i32) -> i64 {
+        let time: Vec<i64> = time.iter().map(|x| *x as i64).collect();
+        let total_trips = total_trips as i64;
+        
+        let check = |t: i64| -> bool {
+            let mut trips = 0;
+            
+            for &bus in time.iter() {
+                trips += t / bus;
+            }
+            
+            trips >= total_trips
+        };
+        
+        let mut left = 0;
+        let mut right = time[0] * total_trips;
+        
+        while left < right {
+            let middle = (right - left) / 2 + left;
+            
+            if check(middle) {
+                right = middle;
+            } else { 
+                left = middle + 1;
+            }
+        }
+        
+        right
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_2187() {
+        assert_eq!(3, Solution::minimum_time(vec![1,2,3], 5));
+        assert_eq!(2, Solution::minimum_time(vec![2], 1));
+    }
+}