UVA 10285 - Longest Run on a Snowboard

#include <cstdio>
#include <algorithm>
#include <iostream>
#include <cstring>
#include <cmath>
#include <cstdlib>
#include <string>
#include <map>
#include <vector>
#include <set>
#include <queue>
#include <stack>
#include <cctype>
using namespace std;
#define ll long long
#define maxn 150+10
#define INF 1<<30
int d[5][3] = {{-1,0},{1,0},{0,-1},{0,1}};
struct po{
    int x,y;
    int v;
    friend bool operator < (po a, po b){
        return a.v < b.v;
    }
};
int main (){
    int counts;
    scanf("%d",&counts);
    while(counts--){
        string s;
        cin >> s;
        int m,n;
        int map1[maxn][maxn];
        int step[maxn][maxn] = {0};
        vector <po> p;
        p.clear();
        scanf("%d%d",&m,&n);
        for(int i = 0; i < m; i++){
            for(int j = 0; j < n; j++){
                scanf("%d",&map1[i][j]);
                po x;
                x.v = map1[i][j];
                x.x = i;
                x.y = j;
                p.push_back(x);
            }
        }
        sort(p.begin(),p.end());
        int ma = -1;
        for(int i = 0; i < m * n; i++){
            int flag = 0;
            for(int j = 0; j < 4; j++){
                int xx = p[i].x + d[j][0];
                int yy = p[i].y + d[j][1];
                if(xx >=0 && xx < m && yy >= 0 && yy < n){
                    if(map1[p[i].x][p[i].y] > map1[xx][yy]){
                        flag = 1;
                        step[p[i].x][p[i].y] = max(step[p[i].x][p[i].y], step[xx][yy] + 1);
                    }
                }
            }
            if(!flag)
                step[p[i].x][p[i].y] += 1;
            ma = max(step[p[i].x][p[i].y], ma);
        }
        cout << s << ": ";
        printf("%d\n",ma);
    }
    return 0;
}