1091 added.

1091-Shortest-Path-in-Binary-Matrix/cpp-1091/CMakeLists.txt

@@ -0,0 +1,6 @@
+cmake_minimum_required(VERSION 3.14)
+project(C)
+
+set(CMAKE_CXX_STANDARD 14)
+
+add_executable(C main.cpp)

1091-Shortest-Path-in-Binary-Matrix/cpp-1091/main.cpp

@@ -0,0 +1,64 @@
+/// Source : https://leetcode.com/problems/shortest-path-in-binary-matrix/
+/// Author : liuyubobobo
+/// Time   : 2019-06-15
+
+#include <iostream>
+#include <vector>
+#include <queue>
+
+using namespace std;
+
+
+/// BFS
+/// Time Complexity: O(n * m)
+/// Space Complexity: O(n * m)
+class Solution {
+
+private:
+    const int d[8][2] = {{1, 0}, {-1, 0}, {0, 1}, {0, -1},
+                         {1, 1}, {1, -1}, {-1, 1}, {-1, -1}};
+    int n, m;
+
+public:
+    int shortestPathBinaryMatrix(vector<vector<int>>& grid) {
+
+        if(grid[0][0]) return -1;
+
+        n = grid.size(), m = grid[0].size();
+        vector<vector<int>> res(n, vector<int>(m, -2));
+
+        queue<int> q;
+        res[0][0] = 0;
+        q.push(0);
+        while(!q.empty()){
+            int x = q.front() / m;
+            int y = q.front() % m;
+            q.pop();
+
+            for(int i = 0; i < 8; i ++){
+                int newX = x + d[i][0], newY = y + d[i][1];
+                if(newX >= 0 && newX < n && newY >= 0 && newY < m &&
+                   grid[newX][newY] == 0 && res[newX][newY] == -2){
+                    res[newX][newY] = res[x][y] + 1;
+                    q.push(newX * m + newY);
+                }
+            }
+        }
+
+//        for(int i = 0; i < n; i ++){
+//            for(int j = 0; j < m; j ++)
+//                cout << res[i][j] << " ";
+//            cout << endl;
+//        }
+        return res[n - 1][m - 1] + 1;
+    }
+};
+
+
+int main() {
+
+    vector<vector<int>> grid = {{0,0,0},{1,1,0},{1,1,0}};
+    cout << Solution().shortestPathBinaryMatrix(grid) << endl;
+
+    return 0;
+}

readme.md

@@ -741,4 +741,5 @@ email: [[email protected]](mailto:[email protected])
 | | | | | | |
 | 1089 | [Duplicate Zeros](https://leetcode.com/problems/duplicate-zeros/) | [无] | [C++](1089-Duplicate-Zeros/cpp-1089/) | | |
 | 1090 | [Largest Values From Labels](https://leetcode.com/problems/largest-values-from-labels/) | [无] | [C++](1090-Largest-Values-From-Labels/cpp-1090/) | | |
+| 1091 | [Shortest Path in Binary Matrix](https://leetcode.com/problems/shortest-path-in-binary-matrix/) | [无] | [C++](1091-Shortest-Path-in-Binary-Matrix/cpp-1091/) | | |
 | | | | | | |