记忆化搜索，每个位置都往下搜，搜索到最低点，然后可以依次计算路径上每个点的高度。

#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;

int depth(vector<vector<int>>& area, vector<vector<int>>& f, int i, int j) {
    if (f[i][j]) return f[i][j];
    int m = area.size() - 1, n = area[0].size() - 1;
    int u = (i > 0  && area[i-1][j] < area[i][j]) ? depth(area, f, i-1, j) + 1 : 0;
    int d = (i < m  && area[i+1][j] < area[i][j]) ? depth(area, f, i+1, j) + 1 : 0;
    int l = (j > 0  && area[i][j-1] < area[i][j]) ? depth(area, f, i, j-1) + 1 : 0;
    int r = (j < n  && area[i][j+1] < area[i][j]) ? depth(area, f, i, j+1) + 1 : 0;
    f[i][j] = max({u, d, l ,r});
    return f[i][j];
}

int main(int argc, char* argv[]) {
    int r, c;
    scanf("%d %d", &r, &c);
    vector<vector<int>> area(r, vector<int>(c, 0));
    for (int i = 0; i < r; ++i) {
        for (int j = 0; j < c; ++j) {
            scanf("%d", &area[i][j]);
        }
    }
    int ans = 0;
    vector<vector<int>> f(r, vector<int>(c, 0));
    for (int i = 0; i < r; ++i) {
        for (int j = 0; j < c; ++j) {
            if (!f[i][j]) ans = max(ans, depth(area, f, i, j) + 1);
        }
    }
    printf("%d\n", ans);
    return 0;
}

original refer