leetcode Longest Increasing Path in a Matrix

题意：给定一个矩阵，在里面找出最大上升路径

int dx[] = { 1 , -1, 0 , 0 };
int dy[] = { 0 , 0 , 1 , -1 };
class Solution {
public:
int dfs(int x, int y, const int &m,const int &n,vector<vector<int>>& matrix, vector<vector<int>>& dis) {
if (dis[x][y]) return dis[x][y];

for (int i = 0; i < 4; i++) {
int nx = x + dx[i];
int ny = y + dy[i];
if (nx >= 0 && ny >= 0 && nx < m && ny < n && matrix[nx][ny] > matrix[x][y]) {
dis[x][y] = max(dis[x][y], dfs(nx, ny, m, n, matrix, dis));
}
}
dis[x][y]++;
return dis[x][y];
}

int longestIncreasingPath(vector<vector<int>>& matrix) {
if (!matrix.size()) return 0;
int m = matrix.size(), n = matrix[0].size();
vector<vector<int> > dis(m, vector<int>(n, 0));
int ans = 0;
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
ans = max(ans, dfs( i, j, m, n, matrix, dis));
}
}
return ans;
}
};

本文是leetcode 329 Longest Increasing Path in a Matrix  的题解，更多题解可见

https://www.hrwhisper.me/leetcode-algorithm-solution/

本博客若无特殊说明则由 hrwhisper 原创发布

出处：细语呢喃 > leetcode
Longest Increasing Path in a Matrix

地址：https://www.hrwhisper.me/leetcode-longest-increasing-path-matrix/