function plotTour(positions, route)
    % 绘制遍历路径的示意图
    % 输入：positions - 包含城市坐标的矩阵
    %      route - 遍历路径
    
    % 创建新图形窗口
    figure;
    
    % 绘制所有城市点
    plot(positions(:, 2), positions(:, 3), 'o', 'MarkerSize', 8, 'MarkerFaceColor', 'blue');
    hold on;
    
    % 绘制路径连线
    for i = 1:length(route)-1
        current = route(i);
        next = route(i+1);
        
        % 绘制从当前城市到下一个城市的线
        line([positions(current, 2), positions(next, 2)], ...
             [positions(current, 3), positions(next, 3)], ...
             'Color', 'red', 'LineWidth', 1.5);
    end
    
    % 标记起点和终点（相同城市）
    plot(positions(route(1), 2), positions(route(1), 3), 'gs', 'MarkerSize', 12, 'MarkerFaceColor', 'green');
    
    % 添加城市标签
    for i = 1:size(positions, 1)
        text(positions(i, 2), positions(i, 3), num2str(i), ...
             'HorizontalAlignment', 'left', 'VerticalAlignment', 'bottom');
    end
    
    % 添加图例和标题
    xlabel('X坐标');
    ylabel('Y坐标');
    title('城市遍历路径');
    grid on;
    legend('城市', '路径', '起点/终点');
    hold off;
end