java - 接收和返回方法

Question

我正在尝试编写一个简单的程序，该程序调用各种方法来提示用户输入他们的城市和州名称以及人口，而不是给出人口的百分比。我已经得到了大部分代码，但我不断收到 1 个编译器错误，上面写着

"Error: cannot find symbol, variable: cityPercState"

有人可以告诉我我的代码有什么问题吗？

import java.util.Scanner;

public class CityOrozcoB52 
{ // begin class
  private static Scanner input = new Scanner(System.in);

  public static void main(String[] args) 
  { // begin main method

    String city, state;
    float cityPopulation, statePopulation;



    cityName();
    stateName();
    cityPopulation(city);
    statePopulation(state);
    cityPercState(cityPopulation, statePopulation);
    displayCityStateStats(city, state, cityPopulation, statePopulation, cityPercState);



 } // end main method

  public static String cityName()
  {
    String city = "";
    System.out.printf("What is the name of your city:");
     city = input.nextLine();

     return city;
  }

  public static String stateName()
  {
    String state = "";
    System.out.printf("What is the name of your state:");
    state = input.nextLine();

    return state;
  }

  public static float cityPopulation(String city)
  {
    float cityPopulation = 0;
    System.out.printf("what is the population of %s:\n", city);
    cityPopulation = input.nextFloat();

    return cityPopulation; 
  }
  public static float statePopulation(String state)
  {
    float statePopulation = 0;
    System.out.printf("what is the population of %s:", state);
    statePopulation = input.nextFloat();

    return statePopulation;
  }

  public static float cityPercState(float cityPopulation, float statePopulation)
  {
   float cityStatePercentage = (cityPopulation / statePopulation) * 100; 
  }

  public static void displayCityStateStats(String cityName, String stateName, float cityPopulation, float statePopulation, 
                                      float cityPercState)
  {
   System.out.printf("POPULATION STATISTICS\n\n"
                    + "City: %s"
                    + "State: %s"
                    + "City Population: %f"
                    + "State Population: %f"
                    + "City to State Population: %.2f%%", cityName, stateName, cityPopulation, statePopulation, 
                                                          cityPercState);

  }
} // ends CityOrozcoLE52

Answer 1

您实际上需要在 cityPercState() 方法中返回一个值。

所以添加:

return cityStatePercentage; 

到方法。