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Practice Shortest Bridge

Read the task, work through the examples, and check your approach against the constraints. Use the original LeetCode task for coding and submissions.

Medium#934
LeetCode Problem

Shortest Bridge

ArrayDepth-First SearchBreadth-First SearchMatrix

Problem Statement

You are given an n x n binary matrix grid where 1 represents land and 0 represents water. An island is a 4-directionally connected group of 1's not connected to any other 1's. There are exactly two islands in grid. You may change 0's to 1's to connect the two islands to form one island. Return the smallest number of 0's you must flip to connect the two islands.

Source: Shortest Bridge on LeetCode. Use the original task for its coding environment and submissions.

Examples

# Example 1

Input
grid = [[0,1],[1,0]]
Output
1

# Example 2

Input
grid = [[0,1,0],[0,0,0],[0,0,1]]
Output
2

# Example 3

Input
grid = [[1,1,1,1,1],[1,0,0,0,1],[1,0,1,0,1],[1,0,0,0,1],[1,1,1,1,1]]
Output
1

Constraints

n == grid.length == grid[i].length
2 <= n <= 100
grid[i][j] is either 0 or 1.
There are exactly two islands in grid.

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