leetcode

Solution to some Leetcode problems written in C++

git clone git://git.dimitrijedobrota.com/leetcode.git

commit	1c5c912fcef26b4a5a3b14534dcc94149bd47a20
parent	b0a5a3da4551a99057f6694e0981d1109203cf27
author	Dimitrije Dobrota <mail@dimitrijedobrota.com>
date	Fri, 7 Apr 2023 08:38:18 +0200

Daily Problem

Diffstat:

A	Problems/1020.cpp	\|	+++++++++++++++++++++++++++++++++++++
M	README.md	\|	+

2 files changed, 38 insertions(+), 0 deletions(-)

diff --git a/Problems/1020.cpp b/Problems/1020.cpp

@@ -0,0 +1,37 @@

class Solution {

int n, m;

bool valid(int x, int y) { return x >= 0 && x < n && y >= 0 && y < m; }

int flood_fill(vector<vector<int>> &grid, int x, int y) {

grid[x][y] = 0;

int count = 1;

if (valid(x + 1, y) && grid[x + 1][y]) count += flood_fill(grid, x + 1, y);

if (valid(x - 1, y) && grid[x - 1][y]) count += flood_fill(grid, x - 1, y);

if (valid(x, y + 1) && grid[x][y + 1]) count += flood_fill(grid, x, y + 1);

if (valid(x, y - 1) && grid[x][y - 1]) count += flood_fill(grid, x, y - 1);

return count;

}

public:

int numEnclaves(vector<vector<int>> &grid) {

n = grid.size(), m = grid[0].size();

for (int i = 0; i < n; i++) {

if (grid[i][0]) flood_fill(grid, i, 0);

if (grid[i][m - 1]) flood_fill(grid, i, m - 1);

}

for (int i = 0; i < m; i++) {

if (grid[0][i]) flood_fill(grid, 0, i);

if (grid[n - 1][i]) flood_fill(grid, n - 1, i);

}

int res = 0;

for (int i = 1; i < n - 1; i++) {

for (int j = 1; j < m - 1; j++) {

if (!grid[i][j]) continue;

res += flood_fill(grid, i, j);

}

return res;

}

};

diff --git a/README.md b/README.md

@@ -380,6 +380,7 @@ for solving problems.

| 1011 | Medium | [Capacity To Ship Packages Within D Days](Problems/1011.cpp) |

| 1014 | Medium | [Best Sightseeing Pair](Problems/1014.cpp) |

| 1019 | Medium | [Next Greater Node In Linked List](Problems/1019.cpp) |

| 1020 | Medium | [Number of Enclaves](Problems/1020.cpp) |

| 1022 | Easy | [Sum of Root To Leaf Binary Numbers](Problems/1022.cpp) |

| 1026 | Medium | [Maximum Difference Between Node and Ancestor](Problems/1026.cpp) |

| 1038 | Medium | [Binary Search Tree to Greater Sum Tree](Problems/1038.cpp) |