Class Solution
Medium
Bob is stuck in a dungeon and must break n locks, each requiring some amount of energy to break. The required energy for each lock is stored in an array called strength where strength[i] indicates the energy needed to break the ith lock.
To break a lock, Bob uses a sword with the following characteristics:
- The initial energy of the sword is 0.
- The initial factor
Xby which the energy of the sword increases is 1. - Every minute, the energy of the sword increases by the current factor
X. - To break the
ithlock, the energy of the sword must reach at leaststrength[i]. - After breaking a lock, the energy of the sword resets to 0, and the factor
Xincreases by a given valueK.
Your task is to determine the minimum time in minutes required for Bob to break all n locks and escape the dungeon.
Return the minimum time required for Bob to break all n locks.
Example 1:
Input: strength = [3,4,1], K = 1
Output: 4
Explanation:
| Time | Energy | X | Action | Updated X |
|---|---|---|---|---|
| 0 | 0 | 1 | Nothing | 1 |
| 1 | 1 | 1 | Break 3rd Lock | 2 |
| 2 | 2 | 2 | Nothing | 2 |
| 3 | 4 | 2 | Break 2nd Lock | 3 |
| 4 | 3 | 3 | Break 1st Lock | 3 |
The locks cannot be broken in less than 4 minutes; thus, the answer is 4.
Example 2:
Input: strength = [2,5,4], K = 2
Output: 5
Explanation:
| Time | Energy | X | Action | Updated X |
|---|---|---|---|---|
| 0 | 0 | 1 | Nothing | 1 |
| 1 | 1 | 1 | Nothing | 1 |
| 2 | 2 | 1 | Break 1st Lock | 3 |
| 3 | 3 | 3 | Nothing | 3 |
| 4 | 6 | 3 | Break 2nd Lock | 5 |
| 5 | 5 | 5 | Break 3rd Lock | 7 |
The locks cannot be broken in less than 5 minutes; thus, the answer is 5.
Constraints:
n == strength.length1 <= n <= 81 <= K <= 101 <= strength[i] <= 106
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Constructor Summary
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Method Summary
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Constructor Details
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Solution
public Solution()
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Method Details
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findMinimumTime
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