There are N workers in a factory. Each worker packs the same type of product, and for each of them we know the time it takes them to pack one product.
Find out the minimum amount of time the workers need to pack at least K products.
Example:
Input: times = [4, 7, 3, 6, 7, 1], K = 60
Output:30
Explanation:
1st worker packs 7 products in 4 * 7 = 28 units of time
2nd worker packs 4 products in 7 * 4 = 28 units of time
3rd worker packs 10 products in 3 * 10 = 30 units of time
4th worker packs 5 products in 6 * 5 = 30 units of time
5th worker packs 4 products in 7 * 4 = 28 units of time
6th worker packs 30 products in 1 * 30 = 30 units of time
We have 7 + 4 + 10 + 5 + 4 + 30 = 60 total products
in max(28, 28, 30, 30, 28, 30) = 30 units of time
and this is the minimum amount of time
since in 29 units of time we can pack only
7 + 4 + 9 + 4 + 4 + 29 = 57 products
Your algorithm should run in O(n * log(k * T)) time and use O(1) extra space.
The core challenge of this problem is to determine the minimum time required for all workers to collectively pack at least K products. This problem is significant in scenarios where optimizing production time is crucial, such as in manufacturing and logistics.
Potential pitfalls include misunderstanding the distribution of work among workers and not considering the maximum time taken by any single worker as the limiting factor.
To solve this problem, we can use a binary search approach on the time. The idea is to find the minimum time required such that the total number of products packed by all workers is at least K.
1. **Naive Solution**: Iterate through each possible time and check if the workers can pack at least K products. This is not optimal as it can be very slow for large values of K.
2. **Optimized Solution**: Use binary search to find the minimum time. This approach is efficient and meets the required time complexity of O(n * log(k * T)).
1. Initialize the binary search range: `low` as 1 and `high` as the maximum possible time (K * max time per product).
2. Perform binary search: - Calculate the mid-point of the current range. - Calculate the total number of products that can be packed in `mid` time. - If the total is at least K, update `high` to `mid`. - Otherwise, update `low` to `mid + 1`.
3. The minimum time required will be the value of `low` after the binary search completes.
public class Factory {
public static int minTime(int[] times, int K) {
int low = 1;
int high = K * getMax(times);
while (low < high) {
int mid = low + (high - low) / 2;
if (canPackInTime(times, K, mid)) {
high = mid;
} else {
low = mid + 1;
}
}
return low;
}
private static boolean canPackInTime(int[] times, int K, int time) {
int totalProducts = 0;
for (int t : times) {
totalProducts += time / t;
if (totalProducts >= K) {
return true;
}
}
return false;
}
private static int getMax(int[] times) {
int max = times[0];
for (int t : times) {
if (t > max) {
max = t;
}
}
return max;
}
public static void main(String[] args) {
int[] times = {4, 7, 3, 6, 7, 1};
int K = 60;
System.out.println(minTime(times, K)); // Output: 30
}
}
The time complexity of the binary search approach is O(n * log(k * T)), where n is the number of workers, k is the number of products, and T is the maximum time per product. The space complexity is O(1) as we are using a constant amount of extra space.
1. All workers have the same packing time. 2. Only one worker. 3. The number of products K is very small or very large.
Each algorithm handles these edge cases by ensuring the binary search covers all possible times and the total products calculation is accurate.
To test the solution comprehensively, consider a variety of test cases: - Simple cases with a few workers and products. - Edge cases with extreme values. - Randomized cases to ensure robustness.
Using a testing framework like JUnit can help automate and validate these test cases.
1. Break down the problem into smaller parts. 2. Use binary search for optimization problems involving a range of values. 3. Practice similar problems to improve problem-solving skills.
Understanding and solving this problem helps in optimizing production processes. Practice and exploration of similar problems can further enhance problem-solving abilities.
1. [Binary Search Algorithm](https://en.wikipedia.org/wiki/Binary_search_algorithm) 2. [LeetCode Problems](https://leetcode.com/problemset/all/) 3. [GeeksforGeeks Tutorials](https://www.geeksforgeeks.org/)