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#include "leetcode.h"
#include <algorithm>
#include <queue>
#include <utility>
#include <vector>
class Solution {
public:
int shortestPathBinaryMatrix(vector<vector<int>> &grid) {
if (grid[0][0] || grid.back().back())
return -1;
int ans = 2, len = 1, nX = grid[0].size() - 1, nY = grid.size() - 1;
queue<pair<int, int>> qp;
if (!nX && !nY)
return 1 - (grid[0][0] << 1);
qp.push({0, 0});
grid[0][0] = -1;
while (len) {
while (len--) {
auto [cX, cY] = qp.front();
qp.pop();
for (int i = max(0, cX - 1), lmtX = min(cX + 1, nX); i <= lmtX; i++) {
for (int j = max(0, cY - 1), lmtY = min(cY + 1, nY); j <= lmtY; j++) {
if (i == nX && j == nY)
return ans;
if (!grid[j][i]) {
grid[j][i] = -1;
qp.push({i, j});
}
}
}
}
ans++;
len = qp.size();
}
return -1;
}
};
int main() {}
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