#include<iostream>
#include<algorithm>
using namespace std;
int rows, cols;
int dx[4] = { 1,0,-1,0 };
int dy[4] = { 0,1,0,-1 };
int squ[101][101] = { {0} };
int store[101][101] = { {0} };


int dfs(int x, int y) {
	if (store[x][y] != 0) return store[x][y];
	for (int i = 0; i < 4; i++) {
		int tx = x + dx[i];
		int ty = y + dy[i];	
		if (tx >= 0 && ty >= 0 && tx <= cols && ty <= rows) {
			if (squ[x][y] > squ[tx][ty]) {				
				dfs(tx, ty);
				store[x][y] = max(store[x][y], store[tx][ty] + 1);
			}
		}		
	}
	return store[x][y];
}
int main() {
	cin >> rows >> cols;
	for (int i = 0; i < rows; i++) {
		for (int j = 0; j < cols; j++) {
			cin >> squ[i][j];
		}
	}
	int ans = 0;
	for (int i = 0; i < rows; i++) {
		for (int j = 0; j < cols; j++) {
			ans = max(dfs(i, j), ans);		
		}		
	}
	cout << ans + 1;
}

就是这个，找了很久依旧没看出来什么地方出的问题