题目

代码

//#pragma GCC optimize(3)

#include <bits/stdc++.h>
const int N = 310;
using namespace std;
int dx[4] = {-1, 0, 1, 0}, dy[4] = {0, 1, 0, -1};
int ans;
int g[N][N];
int r, c;
int f[N][N];
int dfs(int x, int y)
{
    if(~f[x][y]) return f[x][y];
    f[x][y] = 1;
    
    for(int i = 0; i < 4; i++)
    {
        int nx = x + dx[i], ny = y + dy[i];
        if(nx < 1 || ny < 1 || nx > r || ny > c || g[nx][ny] >= g[x][y]) continue;
        f[x][y] = max(f[x][y], dfs(nx,ny)+1);
    }
    
    return f[x][y];
}
int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    
    cin >> r >> c;
    for(int i = 1; i <= r; i++)
    {
        for(int j = 1; j <= c; j++)
        {
            cin >> g[i][j];
        }
    }
    
    memset(f, -1, sizeof f);
    for(int i = 1; i <= r; i++)
        for(int j = 1; j <= c; j++)
        {
            ans = max(ans, dfs(i,j));
        }
            
    cout << ans;
}