C++11(clang++ 3.9) 解法, 执行用时: 15ms, 内存消耗: 612K, 提交时间: 2020-06-19 17:15:33

#include<iostream>
#include<vector>
#include<algorithm>
#include<string>
#include<queue>
using namespace std;
int n, m;
int xx[4] = { 1,-1,0,0 };
int yy[4] = { 0,0,-1,1 };
struct pos {
    int len;
    int x;
    int y;
};

bool compare(pos a, pos b) {
    if (a.len != b.len) {
        return a.len > b.len ? true : false;
    }
    else {
        return a.x == b.x ? (a.y > b.y) : (a.x > b.x);
    }
}

pos func(int x, int y, const vector<vector<int>>& matrix) {
    pos cur;
    cur.len = 1;
    cur.x = x;
    cur.y = y;
    queue<pos>q;
    q.push(cur);
    while (!q.empty()) {
        pos t = q.front();
        int cur_len = t.len;
        int cur_x = t.x;
        int cur_y = t.y;
        q.pop();
        //int f = 1;
        for (int i = 0; i < 4; i++) {
            int nx = cur_x + xx[i];
            int ny = cur_y + yy[i];
            if (nx >= 0 && nx < n && ny >= 0 && ny<m && matrix[nx][ny]>matrix[cur_x][cur_y]) {
                //f = 0;
                pos temp;
                temp.len = cur_len + 1;
                temp.x = nx;
                temp.y = ny;
                q.push(temp);
            }
        }
        //if (1) {
            if (compare(t, cur)) {
                cur = t;
            }
       // }
    }
    return cur;
}

int main() {
    while (cin >> n >> m) {
        vector<vector<int>>matrix(n, vector<int>(m, 0));
        pos cur;
        cur.len = 0;
        cur.x = 0;
        cur.y = 0;
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++) {
                cin >> matrix[i][j];
            }
        }
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++) {
                pos temp = func(i, j, matrix);
                if (compare(temp, cur)) {
                    cur = temp;
                }
            }
        }
        cout << cur.len << " " << cur.x << " " << cur.y << endl;

    }
    system("pause");
}

C++14(g++5.4) 解法, 执行用时: 8ms, 内存消耗: 496K, 提交时间: 2020-06-17 17:12:30

#include <iostream>
using namespace std;
const int N=45;
int maze[N][N];
int n,m;
int end_x,end_y;
int ans;
int dx[4]={0,-1,1,0};
int dy[4]={1,0,0,-1};
void dfs(int cur_i,int cur_j,int cnt){
    if(cnt>ans||(cnt==ans&&cur_i>end_x)||(cnt==ans&&cur_i==end_x&&cur_j>end_y)){
        end_x=cur_i;end_y=cur_j;ans=cnt;
    }
    for(int i=0;i<4;i++){
        int ii=cur_i+dx[i];
        int jj=cur_j+dy[i];
        if(ii>=0&&jj>=0&&ii<n&&jj<m&&maze[ii][jj]>maze[cur_i][cur_j]){
            dfs(ii,jj,cnt+1);
        }
    }
}
int main() {

    while(cin>>n>>m) {
        for (int i = 0; i < n; i++)
            for (int j = 0; j < m; j++)
                cin >> maze[i][j];
        ans=0;
        for(int i=0;i<n;i++)
            for(int j=0;j<m;j++)
                dfs(i,j,0);
        cout<<ans+1<<" "<<end_x<<" "<<end_y<<endl;
    }
    return 0;
}