leetcode

Solution to some Leetcode problems written in C++
git clone git://git.dimitrijedobrota.com/leetcode.git
Log | Files | Refs | README | LICENSE |
commit4eba76cf87b984de24105cd5516587543be95faf
parentf09f44fa95e8eebd4941c50c9f242f4f33f3a164
authorDimitrije Dobrota <mail@dimitrijedobrota.com>
dateWed, 15 May 2024 14:32:18 +0200

Daily Problem

Diffstat:
AProblems/2812.cpp|+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
MREADME.md|+

2 files changed, 64 insertions(+), 0 deletions(-)

diff --git a/Problems/2812.cpp b/Problems/2812.cpp

@@ -0,0 +1,63 @@

class Solution {
public:
int maximumSafenessFactor(vector<vector<int>> &grid) {
static int offset[] = {-1, 0, 1, 0, -1};
const int n = size(grid);
using qtype_t = tuple<int, int>;
queue<qtype_t> q;
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
if (grid[i][j] != 1) continue;
q.emplace(i, j);
}
}
for (int lvl = 2; !q.empty(); lvl++) {
for (int k = q.size(); k > 0; k--) {
const auto [a, b] = q.front();
q.pop();
for (int k = 0; k < 4; k++) {
const int x = a + offset[k + 1];
const int y = b + offset[k];
if (x < 0 || x >= n || y < 0 || y >= n) continue;
if (grid[x][y]) continue;
grid[x][y] = lvl;
q.emplace(x, y);
}
}
}
using pqtype_t = tuple<int, int, int>;
priority_queue<pqtype_t> pq;
int res = grid[0][0];
pq.emplace(grid[0][0], 0, 0);
grid[0][0] = -grid[0][0];
while (!pq.empty()) {
const auto [v, a, b] = pq.top();
pq.pop();
res = min(res, -grid[a][b]);
if (a == n - 1 && b == n - 1) return res - 1;
for (int k = 0; k < 4; k++) {
const int x = a + offset[k + 1];
const int y = b + offset[k];
if (x < 0 || x >= n || y < 0 || y >= n) continue;
if (grid[x][y] < 0) continue;
pq.emplace(grid[x][y], x, y);
grid[x][y] = -grid[x][y];
}
}
return 0;
}
};

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

@@ -1194,6 +1194,7 @@ for solving problems.

| 2785 | Medium | [Sort Vowels in a String](Problems/2785.cpp) |
| 2799 | Medium | [Count Complete Subarrays in an Array](Problems/2799.cpp) |
| 2807 | Medium | [Insert Greatest Common Divisors in Linked List](Problems/2807.cpp) |
| 2812 | Medium | [Find the Safest Path in a Grid](Problems/2812.cpp) |
| 2816 | Medium | [Double a Number Represented as a Linked List](Problems/2816.cpp) |
| 2840 | Medium | [Check if Strings Can be Made Equal With Operations II](Problems/2840.cpp) |
| 2849 | Medium | [Determine if a Cell Is Reachable at a Given Time](Problems/2849.cpp) |