题解

#include <bits/stdc++.h>
using namespace std;

struct Point {
    int x, y;
    Point(int x, int y) : x(x), y(y) {}
};

const int dx[4] = {2, 1, -1, -2};
const int dy[4] = {1, 2, 2, 1};
int n_bound, m_bound;
int targetX, targetY;
vector<vector<Point>> paths;
bool visited[11][11] = {false}; 

void dfs(int x, int y, vector<Point>& curPath) {
    if (x == targetX && y == targetY) {
        paths.push_back(curPath);
        return;
    }
    
    for (int i = 0; i < 4; ++i) {
        int nx = x + dx[i];
        int ny = y + dy[i];
        if (nx >= 0 && nx <= n_bound && ny >= 0 && ny <= m_bound) {
            if (!visited[nx][ny]) {
                visited[nx][ny] = true;
                curPath.push_back(Point(nx, ny));
                dfs(nx, ny, curPath);
                curPath.pop_back();
                visited[nx][ny] = false;
            }
        }
    }
}

void printPaths() {
    for (int i = 0; i < paths.size(); ++i) {
        cout << setw(3) << i + 1 << ":";
        for (int j = 0; j < paths[i].size(); ++j) {
            if (j > 0) cout << "-->";
            cout << paths[i][j].x << "," << paths[i][j].y;
        }
        cout << endl;
    }
}

int main() {
    int n, m;
    cin >> n >> m;
    n_bound = n;
    m_bound = m;
    targetX = n;
    targetY = m;

    vector<Point> curPath;
    
    visited[2][1] = true;
    curPath.push_back(Point(2, 1));
    dfs(2, 1, curPath);
    visited[2][1] = false;
    curPath.pop_back();
    
    visited[1][2] = true;
    curPath.push_back(Point(1, 2));
    dfs(1, 2, curPath);
    visited[1][2] = false;
    curPath.pop_back();
    
    printPaths();
    
    return 0;
}