Package g2101_2200.s2125_number_of_laser_beams_in_a_bank

Class Solution

java.lang.Object

g2101_2200.s2125_number_of_laser_beams_in_a_bank.Solution

public class Solution
extends Object

2125 - Number of Laser Beams in a Bank\. Medium Anti-theft security devices are activated inside a bank. You are given a **0-indexed** binary string array `bank` representing the floor plan of the bank, which is an `m x n` 2D matrix. `bank[i]` represents the ith row, consisting of `'0'`s and `'1'`s. `'0'` means the cell is empty, while`'1'` means the cell has a security device. There is **one** laser beam between any **two** security devices **if both** conditions are met: * The two devices are located on two **different rows**: r1 and r2, where r1 < r2. * For **each** row `i` where r1 < i < r2, there are **no security devices** in the ith row. Laser beams are independent, i.e., one beam does not interfere nor join with another. Return _the total number of laser beams in the bank_. **Example 1:**  **Input:** bank = ["011001","000000","010100","001000"] **Output:** 8 **Explanation:** Between each of the following device pairs, there is one beam. In total, there are 8 beams: * bank[0][1] -- bank[2][1] * bank[0][1] -- bank[2][3] * bank[0][2] -- bank[2][1] * bank[0][2] -- bank[2][3] * bank[0][5] -- bank[2][1] * bank[0][5] -- bank[2][3] * bank[2][1] -- bank[3][2] * bank[2][3] -- bank[3][2] Note that there is no beam between any device on the 0^th row with any on the 3^rd row. This is because the 2^nd row contains security devices, which breaks the second condition. **Example 2:**  **Input:** bank = ["000","111","000"] **Output:** 0 **Explanation:** There does not exist two devices located on two different rows. **Constraints:** * `m == bank.length` * `n == bank[i].length` * `1 <= m, n <= 500` * `bank[i][j]` is either `'0'` or `'1'`.

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
int	numberOfBeams(String[] bank)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Solution

public Solution()

Method Details

numberOfBeams

public int numberOfBeams(String[] bank)